Vincen wrote: ↑

Sun Apr 26, 2020 6:42 am

What is the tenths digit in the decimal representation of a certain number?

(1) The number is less than \(\dfrac{1}{3}\).
(2) The number is greater than \(\dfrac{1}{4}\).

[spoiler]OA=E[/spoiler]

Source: Official Guide

Target question: What is the tenths digit in the decimal representation of a certain number?

Statement 1: The number is less than 1/3
In other words, the number is less than 0.3333...
There are several values that satisfy this condition. Here are two:
Case a: the number is 0.31, in which case the tenths digit is 3
Case b: the number is 0.29, in which case the tenths digit is 2
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT

Statement 2: The number is greater than 1/4
In other words, the number is greater than 0.25
There are several values that satisfy this condition. Here are two:
Case a: the number is 0.31, in which case the tenths digit is 3
Case b: the number is 0.29, in which case the tenths digit is 2
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT

Statements 1 and 2 combined
So, we now now that the number is greater than 0.25 and less than 0.3333..
There are still several values that satisfy this condition. Here are two:
Case a: the number is 0.31, in which case the tenths digit is 3
Case b: the number is 0.29, in which case the tenths digit is 2
Since we cannot answer the target question with certainty, the combined statements are NOT SUFFICIENT

Answer: E

Cheers,
Brent