Swap the percentage round

18% of 50 is hard. 50% of 18 is easy. They are the same answer.

The question

What is 18% of 50?

The trick

a% of b always equals b% of a. If one way looks hard, flip it round.

Worked example

118% of 50 looks awkward
2Flip it: 50% of 18
350% just means half, so the answer is 9

So: 9

Remember it like this

Percentages are polite — they swap places whenever you ask.

In the exam

Look for a friendly number to move into the percentage slot: 25, 50, 10 or 100. If either number is one of those, flipping turns the whole question into one step.

Why it works

a% of b is (a × b) ÷ 100, and b% of a is (b × a) ÷ 100. Multiplication doesn't care about order, so the two are identical.

Explain this to my childGet the words to teach it, in your language

Try it yourself

0/4 correct

1
8% of 25
8% of 25
2
4% of 75
4% of 75
3
12% of 50
12% of 50
4
16% of 25
16% of 25