Problem Solving

M7MBA wrote:Q is a set of four distinct prime numbers. If the sum of the integers in Q is even and the number x is a member of Q, then what is the least value that x can be?

A. 2
B. 3
C. 4
D. 5
E. 7

We need to minimize the four distinct prime numbers.

We're told that the SUM of the four numbers is EVEN.
This means ALL FOUR prime numbers must be odd

ASIDE: We know this because there is only one even prime number (2). Since the four numbers are distinct, there can be, AT MOST, one 2. However, if there were one 2 (and three other odd primes), the sum of the four numbers would be ODD). So, we can conclude that the number 2 is NOT in the set of values.

So, the SMALLEST set of values is: {3, 5, 7, 11}

The number x is a member of Q, then what is the least value that x can be?
Answer: 3 (B)

M7MBA wrote:Q is a set of four distinct prime numbers. If the sum of the integers in Q is even and the number x is a member of Q, then what is the least value that x can be?

A. 2
B. 3
C. 4
D. 5
E. 7

Since the sum of the integers is even, we must have 4 odd prime numbers. Thus, the least value of x is 3.

Answer: B