XAT 2014 — QA & DI Question 9
Simple EquationsEasy
Consider four natural numbers: x, y, x + y, and x – y. Two statements are provided below:
- All four numbers are prime numbers.
- The arithmetic mean of the numbers is greater than 4.
Which of the following statements would be sufficient to determine the sum of the four numbers?
Answer & solution
Statement I.
- B
Statement II.
- C
Statement I and Statement II.
- D
Neither Statement I nor Statement II.
- E
Either Statement I or Statement II.
Solution
Considering Statement I:
Since this is the only possible solution, statement I is sufficient.
Considering Statement II:
âââââââ
Since no unique solution is possible, statement II is not sufficient.
Hence, option (a).