If the average (arithmetic mean) of 3 integers x, y, z is 10, what is

Question

If the average (arithmetic mean) of 3 integers x, y, z is 10, what is the value of z?

(1) x = 1
(2) x = 5 - y

gmatophobia · Answer

Given :
x + y + z = 30

Question :
z = ?

Statement 1

(1) x = 1

The statement alone is not sufficient. Using statement 1, we know that y + z = 29, however, we can have multiple values of z satisfying the equation.

Eliminate A, and D.

Statement 2

(2) x = 5 - y

x + y = 5

As we know that x + y + z = 30, we can use this statement to find z.

Option B

arnimavarshney10 · Answer

Please see the answer in the picture below.

Answer- B

Posted from my mobile device

nammolestias · Answer

statement 1: insuff 
 
  statement 2:- 5-y+y+z=30 z=25 suff

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