## This is a simple method for solving percentage equations. Use this calculator for business, classroom assignments, when shopping, and in general daily life where percentage calculations are needed.

## What are Percentages?

Percentages are similar to fractions with an important difference. In fractions the whole is represented by the denominator (e.g. the number 5 in the fraction of ^{1}/_{5}) In percentages, the whole is represented by the number 100. In fact, "per cent" means "per 100" or "for each 100."

## How to Solve?

To solve the problem above, let’s convert it into equation form: **63 = 90% x __**

In this example, the number that represents the whole is unknown, which we will call "Y". As a percentage, it would be equal to 100%. Written as a ratio, we would get: **100% : Y**

If a student took a test with a number of questions equal to Y, and they got every answer correct, as a percentage they would get a 100% score on the test.

It is already given in this problem that 63 is equivalent to 90%. Written as a ratio, we would get: **90% : 63**

To see a relationship between these two ratios, let’s combine them into an equation: **100% : Y = 90% : 63**

It is critical that both of the % values should be on the same side of a ratio. For instance, if you decide to put the % value on the right side of a ratio, then the other % value should also be on the right side of its ratio.

"Y : 100% and 63 : 90%" is correct.

"Y : 100% and 90% : 63" is wrong.

Let’s solve the equation for Y by first rewriting it as: **100% / Y = 90% / 63**

Drop the percentage marks to simplify your calculations: **100 / Y = 90 / 63**

Multiply both sides by Y to move Y on the right side of the equation: **100 = ( 90 / 63 ) Y**

Simplifying the right side, we get: **100 = 90 Y**

Dividing both sides of the equation by 90, we will arrive at: **70 = Y**

This leaves us with our final answer: **63 is 90% of 70**