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[Smart Math] Arithmetic Problem 6

Here’s and example of a SMART MATH problem for ARITHMETIC.

Problem

Find the greatest three digit number which when divided by 2, 3, 4 and 5 leaves a remainder of 1, 2, 3 and 4 respectively.

1. 939
2. 959
3. 969
4. 949
5. 929

The Usual Method

First get the LCM of 2, 3, 4 and 5 which is 60. Since the remainders are 1 less than the dividends; the number should be = (n x 60) – 1

The greatest value of ‘n’ for (n x 60) – 1 to be a 3 digit number = 16

$\because$16 x 60 – 1 = 960 – 1 = 959

(Ans: 2)

Estimated Time to arrive at the answer = 75 seconds.