Maths Olympiad Prep

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Number theory Difficulty 3.9 AMC 10/12 Find the answer Philippines

Problem:
What is the smallest number that is greater than 20152015 and divisible by both 66 and 3535?

A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.

Solution

Solution:
The desired number is divisible by 22, 33, 55 and 77. Hence, it is the least multiple of 2×3×5×7=2102 \times 3 \times 5 \times 7 = 210 that is greater than 20152015. The desired number is 21002100.

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Source: MathNet, licensed CC-BY-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project.