## Math Tests - mathematics practice questions

Dividing a number in a given ratio (decimals and fractions)

Divide 0.21 in the ratio 3 : 4

Ratio word problems (difficult)

The angles in a triangle are in the ratio 4:3:2. Find the size of the largest angle.

Direct variation word problems (easy)

The total cost of 4 chairs is 700 . How much will 6 chairs cost?

Writing decimals as percents

# How to calculate percentages

A percentage is a fraction whose denominator (bottom number) is always 100. It is denoted using the percent sign (%) or the abbreviations pct. So 1% is 1/100. If we say 20%, we mean 20/100 = 1/5. So 25% means 1/4 and 50% means 1/2

If you have to turn a percentage into a decimal, just divide by 100. For example, 25% = 25/100 = 0.25

If you have to turn a percentage into a fraction, just add 100 as a denominator. For example, 50% = 50/100 = 1/2

The following examples show how to calculate percentages:

3 is what percent of 12?

What is 20% of 80?

8 is 40% percent of what number?