Is the sum of two integers divisible by 10 ?

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BTGModeratorVI wrote:
Mon Apr 13, 2020 3:49 pm
Is the sum of two integers divisible by 10 ?

(1) One of the integers is even.
(2) One of the integers is a multiple of 5.

Answer: E
Source: Official guide
Target question: Is the sum of two integers divisible by 10 ?

Statement 1: One of the integers is even.
We only have information about ONE number.
Statement 1 is NOT SUFFICIENT

Statement 2: One of the integers is a multiple of 5.
We only have information about ONE number.
Statement 2 is NOT SUFFICIENT

Statements 1 and 2 combined
There are many possible pairs of values that satisfy BOTH statements. Here are two:
Case a: The numbers are 10 (even) and 10 (divisible by 5). So, the sum = 20, which means the answer to the target question is YES, the sum of the integers IS divisible by 10.
Case b: The numbers are 2 (even) and 15 (divisible by 5). So, the sum = 17, which means the answer to the target question is NO, the sum of the integers is NOT divisible by 10.
Since we cannot answer the target question with certainty, the combined statements are NOT SUFFICIENT

Answer: E

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