Now that the table with the fractions is provided, we can solve this GMAT Data Sufficiency problem definitively.
The table gives the following fractions of the total pages:
T1: 11/60
T2: 2/15
T3: 7/30
T4: 3/10
T5: 3/20
First, let's convert all fractions to a common denominator (60) to make comparisons easier:
T1: 11/60
T2: 2/15 = (2 * 4) / (15 * 4) = 8/60
T3: 7/30 = (7 * 2) / (30 * 2) = 14/60
T4: 3/10 = (3 * 6) / (10 * 6) = 18/60
T5: 3/20 = (3 * 3) / (20 * 3) = 9/60
Let's check the sum of these fractions to ensure it's 1:
11/60 + 8/60 + 14/60 + 18/60 + 9/60 = (11 + 8 + 14 + 18 + 9) / 60 = 60/60 = 1.0. Correct.
The condition given in the stem: More than 1/2 of the total pages are found on the lower shelf.
1/2 in terms of 60ths is 30/60. So, the sum of fractions on the lower shelf must be >30/60.
We need to determine: Is T3 (14/60) found on the lower shelf?
Statement (1): T2 and T4 have been placed on the lower shelf.
Sum of pages for T2 and T4 = T2 + T4 = 8/60 + 18/60 = 26/60.
This sum (26/60) is NOT greater than 30/60.
This means that other books must also be on the lower shelf for the condition to be met.
The remaining books are T1 (11/60), T3 (14/60), and T5 (9/60).
Let's see if T3 must be on the lower shelf.
If T3 is added: 26/60 + 14/60 = 40/60. This is >30/60. (T3 is on lower shelf)
If T1 is added instead of T3: 26/60 + 11/60 = 37/60. This is >30/60. (T3 is NOT on lower shelf)
If T5 is added instead of T3: 26/60 + 9/60 = 35/60. This is >30/60. (T3 is NOT on lower shelf)
Since we can satisfy the condition without T3 being on the lower shelf (e.g., if T1 and T2 and T4 were on lower shelf, or T5 and T2 and T4 were on lower shelf), Statement (1) alone is not sufficient.
Statement (2): T1 and T5 have been placed on the upper shelf.
This means T1 (11/60) and T5 (9/60) are not on the lower shelf.
The books that could be on the lower shelf are T2 (8/60), T3 (14/60), and T4 (18/60).
Let SL be the sum of fractions on the lower shelf.
We know SL >30/60.
Let's test combinations of T2, T3, T4:
T2 + T4 = 8/60 + 18/60 = 26/60. (Not > 30/60)
T2 + T3 = 8/60 + 14/60 = 22/60. (Not > 30/60)
T3 + T4 = 14/60 + 18/60 = 32/60. (This IS > 30/60)
In this case, T3 is on the lower shelf. (YES)
What if only T2 and T4 are on the lower shelf? Sum is 26/60, which is not > 30/60. So, T2 and T4 alone are not sufficient to meet the condition.
What if only T2 and T3 are on the lower shelf? Sum is 22/60, not > 30/60.
What if only T3 and T4 are on the lower shelf? Sum is 32/60, which is > 30/60. In this scenario, T3 is on the lower shelf.
What if T2, T3, and T4 are all on the lower shelf? Sum = 8/60 + 14/60 + 18/60 = 40/60. This is >30/60. In this scenario, T3 is on the lower shelf.
Since we found a scenario (T3 + T4 on lower shelf) where T3 is on the lower shelf, and the condition (SL >30/60) is met, and there are no other combinations of T2, T3, T4 (excluding T1, T5) that satisfy the condition without T3, this statement is sufficient. Let's re-verify.
The maximum sum of pages possible on the lower shelf without T3 is T2 + T4 = 8/60 + 18/60 = 26/60.
Since 26/60 is NOT greater than 30/60, it is impossible to satisfy the condition (lower shelf > 30/60) if T3 is NOT on the lower shelf.
Therefore, T3 must be on the lower shelf for the total pages on the lower shelf to be greater than 30/60.
Statement (2) alone is sufficient.
Re-evaluating Statement (1) after the values are known:
T2 (8/60) and T4 (18/60) are on the lower shelf. Current sum = 26/60.
Remaining books: T1 (11/60), T3 (14/60), T5 (9/60).
We need the lower shelf total to be > 30/60.
Scenario 1: T3 is on the lower shelf. Sum = 26/60 + 14/60 = 40/60. This is > 30/60. (Answer: Yes, T3 is on lower shelf)
Scenario 2: T1 is on the lower shelf, T3 is not. Sum = 26/60 + 11/60 = 37/60. This is > 30/60. (Answer: No, T3 is not on lower shelf)
Since we get both a "Yes" and a "No" answer, Statement (1) is NOT sufficient.
Final Conclusion:
Statement (1) is not sufficient.
Statement (2) is sufficient.
The final answer is B