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Problem #76 · October 11, 2026

Divisibility rules

When a natural number was divided by 1212, the quotient was 1515 and the remainder was 77. Find this number.
  1. A99
  2. B117
  3. C173
  4. D180
  5. E187

WORKED EXAMPLE

Solution

The formula for division with a remainder: dividend == divisor ⋅\cdot quotient ++ remainder. Therefore, the required number is 12⋅15+7=180+7=18712 \cdot 15 + 7 = 180 + 7 = 187. Check: 187:12=15187 : 12 = 15, remainder 77 and 7<127 < 12 — the condition is satisfied.
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