If the number x is obtained by reversing the.....

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If the number x is obtained by reversing the order of the digits in the positive 3-digit integer y, is x > y?

(1) The tens digit of y is 3.
(2) The rightmost digit of x is 1 and the rightmost digit of y is 9.

The OA is the option B.

How can I use the statement (2) to get an answer here? Experts, can you clarify this for me? I'd be thankful.

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by DrMaths » Thu Jan 25, 2018 7:35 am
Vincen wrote:If the number x is obtained by reversing the order of the digits in the positive 3-digit integer y, is x > y?

(1) The tens digit of y is 3.
(2) The rightmost digit of x is 1 and the rightmost digit of y is 9.

The OA is the option B.

How can I use the statement (2) to get an answer here? Experts, can you clarify this for me? I'd be thankful.
If x = 913, then y=319, so x>y is SUFFICIENT

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by [email protected] » Thu Jan 25, 2018 11:54 am
Hi Vincen,

We're told the positive 3-digit number X is obtained by reversing the order of the digits in the positive 3-digit integer Y. We're asked if X is greater than Y. This is a YES/NO question and we can solve it by TESTing VALUES.

1) The tens digit of Y is 3.

IF... Y = 135, then X = 531, then the answer to the question is YES.
IF... Y = 531, then X = 135, then and the answer to the question is NO.
Fact 1 is INSUFFICIENT.

2) The rightmost digit of X is 1 and the rightmost digit of Y is 9.

The information in Fact 2 'locks in' the first and third digits of each number (meaning that X will always be 9 _ 1 and Y will always be 1 _ 9):

IF... Y = 139, then X = 931, then the answer to the question is YES.
This mean that Y will always be in the 100s and X will always be in the 900s, so the answer to the question is ALWAYS YES.
Fact 2 is SUFFICIENT.

Final Answer: B

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