BTGModeratorVI wrote: ↑Thu Aug 27, 2020 12:22 pm
What is the remainder when integer n is divided by 10?
(1) When n is divided by 110 the remainder is 75.
(2) When n is divided by 100 the remainder is 25.
Answer:
D
Source: Princeton Review
Target question: What is the remainder when integer n is divided by 10?
REPHRASED target question: What is the UNITS DIGIT of n?
Statement 1: When n is divided by 110 the remainder is 75.
In other words: n = 110k + 75 (for some integer k)
Since 110k will have units digit 0 for ANY integer k, we know that 110k + 75 MUST have a units digit of 5
In other words,
n MUST have a units digit of 5
Since we can answer the
REPHRASED target question with certainty, statement 1 is SUFFICIENT
Statement 2: When n is divided by 100 the remainder is 25
In other words: n = 100k + 25 (for some integer k)
Since 100k will have units digit 0 for ANY integer k, we know that 100k + 25 MUST have a units digit of 5
In other words,
n MUST have a units digit of 5
Since we can answer the
REPHRASED target question with certainty, statement 2 is SUFFICIENT
Answer: D
Cheers,
Brent
