Quarter of 100
How to multiply by 25 mentally
Because 25 is one quarter of 100, a multiplication by 25 can often become a division by 4 followed by a multiplication by 100. It is especially fast when the other factor is divisible by 4.
The pattern
n × 25 = (n ÷ 4) × 100
Step by step
- 1Check whether the other factor is easy to divide by 4.
- 2Divide that factor by 4.
- 3Multiply the result by 100 by appending two zeros.
Worked examples
24 × 25
(24 ÷ 4) × 100
600
36 × 25
(36 ÷ 4) × 100
900
52 × 25
(52 ÷ 4) × 100
1,300
If the factor is not divisible by 4, you can still multiply it by 100 and divide the result by 4. Choose the order that feels easiest for the number in front of you.
Try the pattern
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