Year 7 Interactive Maths - Second Edition

Expressing a Quantity as a Percentage of another Quantity

To express one quantity as a percentage of another, make sure that both quantities are expressed in the same units.  Write the given quantity as a fraction of the total and multiply it by 100%.  Then simplify.

Example 9

I obtained 30 marks out of 40 in a test.  Convert this test mark into a percentage.

Solution:

Example 10

What percentage of $4 is 32¢?

Solution:

Note:

To express one quantity as a percentage of another, we must have both quantities in the same units.