Worked example 1 (i) Which is larger, 23% of 150 or 22% of 159? (ii) What percent is 100 millimetres of 4 metres? (iii) In a car park, 60% of all the cars are blue. If there are 240 blue cars, how many cars in total are in the car park?
Solution (i)
(ii)
(iii)
Converting between fractions, decimals and percentages
Fractions, decimals, and percentages are three ways to describe parts of one whole. ●
● ●
A fraction can be written as a decimal or a percentage. A decimal can be written as a fraction or a percentage. A percentage can be written as a fraction or a decimal.
× 100
_ 1
simplify add a % sign Fraction
___ 100
25
0·25 ÷100
(move the decimal point two places to the left)
Percentage put number over 100
remove % sign simplify
× 100 (move decimal point
two places to the right) add a % sign
Decimal
25%
Section A Introducing concepts and building skills