# Math Assignment Help With Determining Percentage

## 14.3 Determining Percentage

• Divide the first number by the second
• Multiply the answer by 100 (Move decimal point two places to the right)
• Round to the desired precision

For example: what is the percentage of 64 in 87

64 / 87 = 0.7356

0.7356 x 100 = 73.56

74(rounded to the nearest whole number)

## 64 is 74% of 87

Percentages are correctly used to express fractions of the total. For example, 25% means 25 / 100, or one quarter, %

To find the percentage of a single unit in a whole of N units, divide 100% by N.

For example, if you have 15 red balls, what percentage of these red balls, one red ball represents.

(100/15)%

= 6.66%

Calculating percentage of a percentage: Convert both percentages to fractions of 100, or into decimals, and then multiply them.

For example, 20% of 70% is:

(20 / 100) × (70 / 100)

= 0.20 × 0.70

= 14 / 100

Dividing by 100 and using the percent sign at the same time is not right

25% = 25 / 100 = 0.25

Not 25% / 100

Which actually are (25 / 100) / 100 = 0.0025