This question is from the bell curves question bank(Answer according to bell curves database is B.

If b is a positive number less than 1, is the tenths digit of b greater than 6?

(1) b + 0.41 > 1
(2) b + 0.39 < 1

MY SOLUTION :

Statement 1 analysis -

B + 0.41 > 1

B > 1 - 0.41

B > 0.59

Which means B can take a value such as 0.591,0.592,0.593 or it can take a value such as 0.61, 0.62 and so on.
Thus, the tenth digit can be 5 or 6. Thus statement 1 is not sufficient on its own.

Statement 2 analysis -

B + 0.39 < 1

B < 0.61

Which means B can take a value such as 0.591,0.592,0.593 or it can take a value such as 0.60, 0.601 and so on.
Thus, the tenth digit can be 5 or 6. Thus statement 2 is not sufficient on its own.

If you combine both the statements then, the range of B turns out to be 0.59<B<0.61

Again, B can take any value such as 0.591, 0.592, 0.60, 0.601.

Thus, combining both the statements, they are not sufficient. So, according to me the answer should be E.

Please correct me if my head is in the clouds.