Brain Teasers & Mental Math
Mental math: what is 25 × 32?
Model answer
800.
Shortcut — 25 is 100/4, so multiplying by 25 means: divide by 4, then multiply by 100. 32 / 4 = 8 → 8 × 100 = 800.
Check the long way: 25 × 32 = 25…
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