Q) Is the sum of all the numbers between prime numbers x and y an even or an odd number?
1) x = 3 y = 31
2) y is the largest two digit number, x is even
A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D. EACH statement ALONE is sufficient.
E. Statements (1) and (2) TOGETHER are NOT sufficient.
Answer
To answer data sufficiency questions you don’t have to solve the problem. You just have to find the sufficient condition to prove the answer choice.
Question: sum(x+1, x+2….y1) = Odd or Even
Condition 1: x = 3 y = 31
Sum (4, 5,….30) = odd or Even
You don’t have to solve this but since you are aware of the sequence of numbers between x and y, the answer can be found.
Condition 1 is enough to answer the question
Condition 2: y is the largest twodigit number, x is even
The question mentions that x and y are prime numbers. Condition 2 provides two more additional information about the prime numbers.
Y is the largest twodigit number
Largest...
Categories : Data Sufficiency, Prime Numbers

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