правила нахождения процентов от числа и нахождение процентного выражения числа от другого

Одним из базовых понятий математики является процент. Для того чтобы понять, что такое процент, достаточно разделить заданную целую величину на сто. Одна сотая часть будет одним процентом (обозначается 1%). Как в точных и экономических науках, так и в других сферах жизни проценты используются для обозначения долей по отношению к целому. При этом само целое обозначается как 100%. В некоторых случаях используется при сравнении двух величин: например, иногда стоимость товаров не сравнивается в денежных единицах, а оценивается, на сколько % цена одного товара больше или меньше цены другого. Термин также получил широкое распространение в банковском деле и в большинстве случаев используется в качестве синонима словосочетания «процентная ставка».

Правило нахождения процентов от числа

Вычисление процентных долей от целого – одна из основных математических операций, к тому же часто используемая в повседневной жизни. Правило нахождения процентов от числа гласит о том, что для решения такой задачи его необходимо умножить на указанное в условиях количество %, после чего полученный результат разделить на 100. Также можно разделить число на 100, и полученный результат умножить на заданное количество %. Важно помнить ещё один тезис: если заданный условиями процент превышает 100%, то полученное числовое значение всегда больше исходного (заданного) – и наоборот.

Правило нахождения числа по его проценту

Существует обратное правило нахождения числа по его проценту. Для того чтобы получить результат по такой математической операции (второму из трёх базовых типов задач на процентные вычисления) необходимо указанное в условиях число разделить на заданную процентную величину, после чего полученный результат умножить на 100. При этом первым действием вычисляется количество единиц исходной величины в 1%, а вторым – в целом (то есть в 100%). Если количество % превышает 100, то полученный результат всегда будет меньше числового значения, заданного условиями задачи – и наоборот.

Правило нахождения процентного выражения числа от другого

Третьим базовым типом математических задач на процентные вычисления являются такие задания, в которых необходимо использовать правило нахождения процентного выражения числа от другого (или соотношения двух величин). Оно гласит о том, что для решения необходимо второе число разделить на первое, после чего полученный результат умножить на сто. Подобное соотношение показывает, сколько % одно числовое значение составляет от другого (то есть, фактически речь идёт об отношении между двумя числовыми значениями, выраженном в %).

«Как высчитывать проценты от числа?» – Яндекс.Кью

Что такое процент? Это часть от целого числа.
В чём ещё можно выразить часть от целого числа? В долях от единицы.
Целое число — это сколько процентов? Это 100%.
Можно целое число принять за 1 (единицу)? Можно.
Как найти часть от целого? Чтобы найти часть от числа, нужно целое число умножить на дробь, которая соответствует этой части.
Например. Задача.
Фруктовая корзина содержит яблоки, груши, персики и сливы массой 4 кг. Слив в этой корзине 20%-ов, персиков -10%-ов, груш — 30%-ов. Чему равна масса каждого фрукта в корзине?
Решение
20% — это в долях от единицы 0,2. Почему так? Потому что 1 меньше 100 во сколько раз? Правильно, в 100 раз. Значит, 20 разделить на 100, будет 0,2 (просто запятую переносим на два знака вперёд).
Вся фруктовая корзина — это целое и масса целого 4 кг. Чему будет равна масса 0,2 части этой корзины (это наши 20%)? Надо 4 кг умножить на 0,2. Получится 0,8 кг. Слив в корзине 800 грамм.
Таким же образом находим массу груш и персиков.
4 х 0,3 = 1,2 кг. Столько груш по массе в корзине или это и есть 30%.
4 х 0,1 = 0,4 кг. Столько персиков (10%).
А массу яблок расчитаем, как оставшуюся массу от остальных фруктов:
4 — 0,8 — 1,2 — 0,4 = 1,6 кг.
Когда я училась в школе (в советское время) нам учитель прочитала такой стишок: «Если часть найти желаешь, то на дробь ты умножаешь. Если часть тебе известна, хочешь целое найти, тут уж всем на удивленье делай поскорей деленье!» Эта присказка навечно засела в голове. Вот и вся премудрость!!! Всё! Про проценты.
Осталось про «удивленье». Задача. Раствор соли содержит 16 г соли, что сооветствует 10%-ам. Чему равна масса этого раствора соли?
Решение
Для удобства переведём проценты в доли от единицы. 10% — это 0,1.
Теперь делим: 16 : 0,1 = 160 г. Мы нашли массу этого 10%-го раствора соли. В 160 г 10%-ного раствора соли содержится 16 г соли
Можешь проверить. 160 х 0,1 = 16 г.

Как найти процент от процента

Математическое определение процента, как сотой части целого от заданного числа — несложная задача. Однако, в жизни часто приходится находить решение и в нестандартных ситуациях. Например, когда в виде исходных данных имеется не число, а также процент от числа. Тут вы узнаете как найти процент от процента.

Пример как найти процент от процента

Вопрос «Как определить объем трубы? Если ее длина 200м а диаметр 65мм.» — 4 ответа Инструкция 1 Запишите исходные данные. Дано число и процент от него. Нужно понять как найти процент от процента. Заданное вычисление процента проводят с использованием его упрощенного представления. Так 1% в десятичном выражении равен 0,01 от целого числа.

2 Исходные проценты представьте в виде десятичной дроби. Для этого нужно разделить процент на 100.

3 По аналогии вычисления процента от числа, для вычисления процента от процента помножьте их десятичные значения. В итоге вы получите десятичную дробь выражения процента от процента для заданного числа.

4 Переведите дробь в процентное выражение. Для этого умножьте результат на 100. Полученное число будет являться процентом от заданного процента. Вот теперь вы на примере знаете как определить процент от процента.

Также вас могут заинтересовать статьи про то, что такое эпитеты.

Видео как определить процент от процента

Обратите внимание.
Находим процент от числа. Допустим, нужно найти 36% от числа 283.

Формула как найти процент от процента: X=N/100%×A, где Х — это неизвестная величина; N — известное число, A — исходный процент.

Полезный совет. Например, 7 процентов можно записать как 7/100, как 0,07 или как 7%. Примером самого распространенного типа задач на проценты может служить следующая: «Найти 17% от 80». Чтобы решить эту задачу, нужно вычислить произведение 0,17•80 = 13,60.

Источник — какпросто.ру

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How to find what percent of X is Y.Use the percentage formula: Y / X = P% 90003 90004 Example: What percent of 60 is 12? 90005 90026 90013 Convert the problem to an equation using the percentage formula: Y / X = P% 90014 90013 X is 60, Y is 12, so the equation is 12/60 = P% 90014 90013 Do the math: 12/60 = 0.20 90014 90013 Important! The result will always be in decimal form, not percentage form. You need to multiply the result by 100 to get the percentage.90014 90013 Converting 0.20 to a percent: 0.20 * 100 = 20% 90014 90013 So 20% of 60 is 12. 90014 90013 Double check your answer with the original question: What percent of 60 is 12? 12/60 = 0.20, and multiplying by 100 to get percentage, 0.20 * 100 = 90042 20% 90043 90014 90045 90006 3. How to find X if P percent of it is Y. Use the percentage formula Y / P% = X 90003 90004 Example: 25 is 20% of what number? 90005 90026 90013 Convert the problem to an equation using the percentage formula: Y / P% = X 90014 90013 Y is 25, P% is 20, so the equation is 25/20% = X 90014 90013 Convert the percentage to a decimal by dividing by 100.90014 90013 Converting 20% ​​to a decimal: 20/100 = 0.20 90014 90013 Substitute 0.20 for 20% in the equation: 25 / 0.20 = X 90014 90013 Do the math: 25 / 0.20 = X 90014 90013 X = 125 90014 90013 So 25 is 20% of 125 90014 90013 Double check your answer with the original question: 25 is 20% of what number? 25 / 0.20 = 90042 125 90043 90014 90045 90094 Remember: How to convert a percentage to a decimal 90095 90026 90013 Remove the percentage sign and divide by 100 90014 90013 15.6% = 15.6 / 100 = 0.156 90014 90045 90094 Remember: How to convert a decimal to a percentage 90095 90026 90013 Multiply by 100 and add a percentage sign 90014 90013 0.876 = 0.876 * 100 = 87.6% 90014 90045 90110 90006 Percentage Problems 90003 90004 There are nine variations on the three basic problems involving percentages. See if you can match your problem to one of the samples below.The problem formats match the input fields in the calculator above. Formulas and examples are included. 90005 90094 What is P percent of X? 90095 90026 90013 Written as an equation: Y = P% * X 90014 90013 The ‘what’ is Y that we want to solve for 90014 90013 Remember to first convert percentage to decimal, dividing by 100 90014 90013 Solution: Solve for Y using the percentage formula 90125 90042 Y = P% * X 90043 90014 90045 90094 Example: What is 10% of 25? 90095 90026 90013 Written using the percentage formula: 90042 Y = 10% * 25 90043 90014 90013 First convert percentage to a decimal 10/100 = 0.1 90014 90013 Y = 0.1 * 25 = 2.5 90014 90013 So 10% of 25 is 2.5 90014 90045 90094 Y is what percent of X? 90095 90026 90013 Written as an equation: Y = P%? X 90014 90013 The ‘what’ is P% that we want to solve for 90014 90013 Divide both sides by X to get P% on one side of the equation 90014 90013 Y ÷ X = (P%? X) ÷ X becomes Y ÷ X = P%, which is the same as P% = Y ÷ X 90014 90013 Solution: Solve for P% using the percentage formula 90125 90042 P% = Y ÷ X 90043 90014 90045 90094 Example: 12 is what percent of 40? 90095 90026 90013 Written using the formula: 90042 P% = 12 ÷ 40 90043 90014 90013 P% = 12 ÷ 40 = 0.3 90014 90013 Convert the decimal to percent 90014 90013 P% = 0.3 × 100 = 30% 90014 90013 So 12 is 30% of 40 90014 90045 90094 Y is P percent of what? 90095 90026 90013 Written as an equation: Y = P% * X 90014 90013 The ‘what’ is X that we want to solve for 90014 90013 Divide both sides by P% to get X on one side of the equation 90014 90013 Y ÷ P% = (P% × X) ÷ P% becomes Y ÷ P% = X, which is the same as X = Y ÷ P% 90014 90013 Solution: Solve for X using the percentage formula 90125 90042 X = Y ÷ P% 90043 90014 90045 90094 Example: 9 is 60% of what? 90095 90026 90013 Writen using the formula: 90042 X = 9 ÷ 60% 90043 90014 90013 Convert percent to decimal 90014 90013 60% ÷ 100 = 0.6 90014 90013 X = 9 ÷ 0.6 90014 90013 X = 15 90014 90013 So 9 is 60% of 15 90014 90045 90094 What percent of X is Y? 90095 90026 90013 Written as an equation: P% * X = Y 90014 90013 The ‘what’ is P% that we want to solve for 90014 90013 Divide both sides by X to get P% on one side of the equation 90014 90013 (P% * X) ÷ X = Y ÷ X becomes P% = Y ÷ X 90014 90013 Solution: Solve for P% using the percentage formula 90125 90042 P% = Y ÷ X 90043 90014 90045 90094 Example: What percent of 27 is 6? 90095 90026 90013 Written using the formula: 90042 P% = 6 ÷ 27 90043 90014 90013 6 ÷ 27 = 0.2222 90014 90013 Convert decimal to percent 90014 90013 P% = 0.2222 × 100 90014 90013 P% = 22.22% 90014 90013 So 22.22% of 27 is 6 90014 90045 90094 P percent of what is Y? 90095 90026 90013 Written as an equation: P% × X = Y 90014 90013 The ‘what’ is X that we want to solve for 90014 90013 Divide both sides by P% to get X on one side of the equation 90014 90013 (P% × X) ÷ P% = Y ÷ P% becomes X = Y ÷ P% 90014 90013 Solution: Solve for X using the percentage formula 90125 90042 X = Y ÷ P% 90043 90014 90045 90094 Example: 20% of what is 7? 90095 90026 90013 Written using the formula: 90042 X = 7 ÷ 20% 90043 90014 90013 Convert the percent to a decimal 90014 90013 20% ÷ 100 = 0.2 90014 90013 X = 7 ÷ 0.2 90014 90013 X = 35 90014 90013 So 20% of 35 is 7. 90014 90045 90094 P percent of X is what? 90095 90026 90013 Written as an equation: P% * X = Y 90014 90013 The ‘what’ is Y that we want to solve for 90014 90013 Solution: Solve for Y using the percentage formula 90125 90042 Y = P% * X 90043 90014 90045 90094 Example: 5% of 29 is what? 90095 90026 90013 Written using the formula: 90042 5% * 29 = Y 90043 90014 90013 Convert the percent to a decimal 90014 90013 5% ÷ 100 = 0.05 90014 90013 Y = 0.05 * 29 90014 90013 Y = 1.45 90014 90013 So 5% of 29 is 1.45 90014 90045 90094 Y of what is P percent? 90095 90026 90013 Written as an equation: Y / X = P% 90014 90013 The ‘what’ is X that we want to solve for 90014 90013 Multiply both sides by X to get X out of the denominator 90014 90013 (Y / X) * X = P% * X becomes Y = P% * X 90014 90013 Divide both sides by P% so that X is on one side of the equation 90014 90013 Y ÷ P% = (P% * X) ÷ P% becomes Y ÷ P% = X 90014 90013 Solution: Solve for X using the percentage formula 90125 90042 X = Y ÷ P% 90043 90014 90045 90094 Example: 4 of what is 12%? 90095 90026 90013 Written using the formula: 90042 X = 4 ÷ 12% 90043 90014 90013 Solve for X: X = Y ÷ P% 90014 90013 Convert the percent to a decimal 90014 90013 12% ÷ 100 = 0.12 90014 90013 X = 4 ÷ 0.12 90014 90013 X = 33.3333 90014 90013 4 of 33.3333 is 12% 90014 90045 90094 What of X is P percent? 90095 90026 90013 Written as an equation: Y / X = P% 90014 90013 The ‘what’ is Y that we want to solve for 90014 90013 Multiply both sides by X to get Y on one side of the equation 90014 90013 (Y ÷ X) * X = P% * X becomes Y = P% * X 90014 90013 Solution: Solve for Y using the percentage formula 90125 90042 Y = P% * X 90043 90014 90045 90094 Example: What of 25 is 11%? 90095 90026 90013 Written using the formula: 90042 Y = 11% * 25 90043 90014 90013 Convert the percent to a decimal 90014 90013 11% ÷ 100 = 0.11 90014 90013 Y = 0.11 * 25 90014 90013 Y = 2.75 90014 90013 So 2.75 of 25 is 11% 90014 90045 90094 Y of X is what percent? 90095 90026 90013 Written as an equation: Y / X = P% 90014 90013 The ‘what’ is P% that we want to solve for 90014 90013 Solution: Solve for P% using the percentage formula 90125 90042 P% = Y / X 90043 90014 90045 90094 Example: 9 of 13 is what percent? 90095 90026 90013 Written using the formula: 90042 P% = Y / X 90043 90014 90013 9 ÷ 13 = P% 90014 90013 9 ÷ 13 = 0.6923 90014 90013 Convert decimal to percent by multiplying by 100 90014 90013 0.6923 * 100 = 69.23% 90014 90013 9 ÷ 13 = 69.23% 90014 90013 So 9 of 13 is 69.23% 90014 90045 90006 Related Calculators 90003 90004 Find the change in percentage as an increase or decrease using the Percentage Change Calculator.90005 90004 Solve decimal to percentage conversions with our Decimal to Percent Calculator. 90005 90004 Convert from percentage to decimals with the Percent to Decimal Calculator. 90005 90004 If you need to convert between fractions and percents see our Fraction to Percent Calculator, or our Percent to Fraction Calculator.90005 90006 References 90003 90004 Weisstein, Eric W. «Percent.» From 90435 MathWorld 90436 — A Wolfram Web Resource. 90005 .90000 Percentage Calculator 90001 90002 Please provide any two values ​​below and click the «Calculate» button to get the third value. 90003 90004 90005 Percentage Calculator in Common Phrases 90006 90004 90005 Percentage Difference Calculator 90006 90004 90005 Percentage Change Calculator 90006 90002 Please provide any two values ​​below and click the «Calculate» button to get the third value. 90003 90002 In mathematics, a percentage is a number or ratio that represents a fraction of 100.It is often denoted by the symbol «%» or simply as «percent» or «pct.» For example, 35% is equivalent to the decimal 0.35, or the fraction 90003. 90017 Percentage Formula 90018 90002 Although the percentage formula can be written in different forms, it is essentially an algebraic equation involving three values. 90003 90021 P × V 90022 1 90023 = V 90022 2 90023 90003 90002 P is the percentage, V 90022 1 90023 is the first value that the percentage will modify, and V 90022 2 90023 is the result of the percentage operating on V 90022 1 90023.The calculator provided automatically converts the input percentage into a decimal to compute the solution. However, if solving for the percentage, the value returned will be the actual percentage, not its decimal representation. 90003 90021 EX: P × 30 = 1.5 90003 90002 If solving manually, the formula requires the percentage in decimal form, so the solution for P needs to be multiplied by 100 in order to convert it to a percent. This is essentially what the calculator above does, except that it accepts inputs in percent rather than decimal form.90003 90017 Percentage Difference Formula 90018 90002 The percentage difference between two values ​​is calculated by dividing the absolute value of the difference between two numbers by the average of those two numbers. Multiplying the result by 100 will yield the solution in percent, rather than decimal form. Refer to the equation below for clarification. 90003 90043 90044 90045 Percentage Difference = 90046 90047 90045 × 100 90046 90050 90051 90017 Percentage Change Formula 90018 90002 Percentage increase and decrease are calculated by computing the difference between two values ​​and comparing that difference to the initial value.Mathematically, this involves using the absolute value of the difference between two values, and dividing the result by the initial value, essentially calculating how much the initial value has changed. 90003 90002 The percentage increase calculator above computes an increase or decrease of a specific percentage of the input number. It basically involves converting a percent into its decimal equivalent, and either subtracting (decrease) or adding (increase) the decimal equivalent from and to 1, respectively.Multiplying the original number by this value will result in either an increase or decrease of the number by the given percent. Refer to the example below for clarification. 90003 90021 EX: 500 increased by 10% (0.1) 90004 500 × (1 + 0.1) = 550 90003 90002 500 decreased by 10% 90004 500 × (1 — 0.1) = 450 90003 .90000 Percentage Change — Percentage Increase and Decrease 90001 90002 For an explanation and everyday examples of using percentages generally see our page 90003 Percentages: An Introduction 90004. For more general percentage calculations see our page 90003 Percentage Calculators 90004. 90007 90008 To calculate the percentage increase: 90009 90002 90003 First: 90004 90013 work out the difference (increase) between the two numbers you are comparing. 90014 90007 90002 90003 Increase = New Number — Original Number 90004 90007 90002 90003 Then: 90004 90013 divide the increase by the original number and multiply the answer by 100.90014 90007 90002 90003% increase = Increase ÷ Original Number × 100 90004. 90007 90002 90003 If your answer is a negative number, then this is a percentage decrease. 90004 90007 90008 To calculate percentage decrease: 90009 90002 90003 First: 90004 90013 work out the difference (decrease) between the two numbers you are comparing. 90014 90007 90002 90003 Decrease = Original Number — New Number 90004 90007 90002 90003 Then: 90004 90013 divide the decrease by the original number and multiply the answer by 100.90014 90007 90002 90003% Decrease = Decrease ÷ Original Number × 100 90004 90007 90002 90003 If your answer is a negative number, then this is a percentage increase. 90004 90007 90002 If you wish to calculate the percentage increase or decrease of several numbers then we recommend using the first formula. Positive values ​​indicate a percentage increase whereas negative values ​​indicate percentage decrease. 90007 90062 90063 Percentage Change Calculator 90064 90065 90002 Use this calculator to work out the percentage change of two numbers 90007 90002 More: 90003 Percentage Calculators 90004 90007 90072 90065 90008 Examples — Percentage Increase and Decrease 90009 90002 90003 In January Dylan worked a total of 35 hours, in February he worked 45.5 hours — by what percentage did Dylan’s working hours increase in February? 90004 90007 90002 To tackle this problem first we calculate the difference in hours between the new and old numbers. 45.5 — 35 hours = 10.5 hours. We can see that Dylan worked 10.5 hours more in February than he did in January — this is his 90003 increase 90004. To work out the increase as a percentage it is now necessary to divide the increase by the original (January) number: 90007 90002 90003 10.5 ÷ 35 = 0.3 90004 (See our 90003 division 90004 page for instruction and examples of division.) 90007 90002 Finally, to get the percentage we multiply the answer by 100. This simply means moving the decimal place two columns to the right. 90007 90002 90003 0.3 × 100 = 30 90004 90007 90002 90003 Dylan therefore worked 30% more hours in February than he did in January. 90004 90007 90002 In March Dylan worked 35 hours again — the same as he did in January (or 100% of his January hours). What is the percentage difference between Dylan’s February hours (45.5) and his March hours (35)? 90007 90002 First calculate the decrease in hours, that is: 90003 45.5 — 35 = 10.5 90004 90007 90002 Then divide the decrease by the original number (February hours) so: 90007 90002 90003 10.5 ÷ 45.5 = 0.23 90004 (to two decimal places). 90007 90002 Finally multiply 0.23 by 100 to give 23%. 90003 Dylan’s hours were 23% lower in March than in February. 90004 90007 90002 You may have thought that because there was a 30% increase between Dylan’s January hours (35) and February (45.5) hours, that there would also be a 30% decrease between his February and March hours. As you can see, this assumption is incorrect. 90007 90002 The reason is because our original number is different in each case (35 in the first example and 45.5 in the second). This highlights how important it is to make sure you are calculating the percentage from the correct starting point. 90007 90002 Sometimes it is easier to show percentage decrease as a negative number — to do this follow the formula above to calculate percentage increase — your answer will be a negative number if there was a decrease.In Dylan’s case the 90013 increase 90014 in hours between February and March is -10.5 (negative because it is a decrease). Therefore -10.5 ÷ 45.5 = -0.23. -0.23 × 100 = -23%. 90007 90002 Dylan’s hours could be displayed in a data table as: 90007 90126 90127 90128 Month 90129 90128 Hours 90072 Worked 90129 90128 Percentage 90072 Change 90129 90136 90127 90128 January 90129 90128 35 90 129 90128 90129 90136 90127 90128 February 90 129 90128 45.5 90129 90128 30% 90129 90136 90127 90128 March 90129 90128 35 90 129 90128 -23% 90 129 90136 90161 90065 90063 Calculating Values ​​Based on Percentage Change 90064 90002 Sometimes it is useful to be able to calculate actual values ​​based on the percentage increase or decrease. It is common to see examples of when this could be useful in the media. 90007 90002 You may see headlines like: 90007 90169 90002 UK rainfall was 23% above average this summer. 90072 Unemployment figures show a 2% decline.90072 90003 Bankers 90004 90003 ‘bonuses slashed by 45%. 90004 90007 90178 90002 These headlines give an idea of ​​a trend — where something is increasing or decreasing, but often no actual data. 90007 90002 Without data, percentage change figures can be misleading. 90007 90065 90002 Ceredigion, a county in West Wales, has a very low violent crime rate. 90007 90002 Police reports for Ceredigion in 2011 showed a 100% increase in violent crime. This is a startling number, especially for those living in or thinking about moving to Ceredigion.90007 90002 However, when the underlying data is examined it shows that in 2010 one violent crime was reported in Ceredigion. So an increase of 100% in 2011 meant that two violent crimes were reported. 90007 90002 When faced with the actual figures, perception of the amount of violent crime in Ceredigion changes significantly. 90007 90002 In order to work out how much something has increased or decreased in real terms we need some actual data. 90007 90002 Take the example of «90013 UK rainfall this summer was 23% above average 90014» — we can tell immediately that the UK experienced almost a quarter (25%) more rainfall than average over the summer.However, without knowing either what the average rainfall is or how much rain fell over the period in question we can not work out how much rain actually fell. 90007 90002 Calculating the actual rainfall for the period if the average rainfall is known. 90007 90002 If we know the average rainfall is 250mm, we can work out the rainfall for the period by calculating 250 + 23%. 90007 90002 First work out 1% of 250, 250 ÷ 100 = 2.5. Then multiply the answer by 23, because there was a 23% increase in rainfall.90007 90002 2.5 × 23 = 57.5. 90007 90002 90003 Total rainfall for the period in question was therefore 250 + 57.5 = 307.5mm. 90004 90007 90002 Calculating the average rainfall if the actual amount is known. 90007 90002 If the news report states the new measurement and a percentage increase, «90013 UK rainfall was 23% above average … 320mm of rain fell … 90014». 90007 90002 In this example we know the total rainfall was 320mm. We also know that this is 23% above the average. In other words, 320mm equates to 123% (or 1.23 times) of the average rainfall. To calculate the average we divide the total (320) by 1.23. 90007 90002 320 ÷ 1.23 = 260.1626. 90013 Rounded to one decimal place, the average rainfall is 90003 260.2mm 90004. 90014 90007 90002 The difference between the average and the actual rainfall can now be calculated: 90072 320 — 260.2 = 90003 59.8mm 90004. 90007 90002 We can conclude that 59.8mm is 23% of the average rainfall amount (260.2mm), and that in real terms, 59.8mm more rain fell than average.90007 90065 90002 We hope you have found this page useful — why not check out our other numeracy skills pages? Or let us know about a subject you would like to see on SkillsYouNeed — 90003 Contact Us 90004. 90007 .