Percentages

What is a percentage?

A percentage is a proportion of an amount, group or set

How do you convert fractions to percentages?

• Divide the numerator by the denominator

• Multiply by 100

• eg. 5/8 can be expressed as a percentage by dividing 5 by 8 and multiplying the total by 100= 62.5%

What is the formula for percentage difference?

Difference/total x100

How do you work out percentage increase?

(new value-original value)/original value x100

How do you work out percentage decrease?

(original value-new value)/original value x100

Leo and Sandy are both young Tom cats. They were let out to hunt one night. Leo caught 5 mice and Sandy caught 7. What is the mean number of mice caught by the two cats, and what is the percentage difference between them?

• (7+5)/2 =6

• 7-5= 2 (difference)

• 2/6 × 100= 33.3%