If the product of the integers w, x, y and z is 770, and if 1

Question

If the product of the integers w, x, y and z is 770, and if 1 < w < x < y < z, what is the value of w + z?

A. 10
B. 13
C. 16
D. 18
E. 21

PS28602.01

BrentGMATPrepNow · Accepted Answer

This looks like a job for  prime factorization!

770 = (2)(5)(7)(11)

If 1 < w < x < y < z, then we can see that w =  2 , x = 5, y = 7 and z =  11

So, w + z =  2  +  11  =   13

Answer: B

Cheers,
Brent

subhashghosh · Answer

770 = 2 * 5 * 7 * 11

So w = 2, x = 5, y = 7, z = 11

w + z = 2 + 11 = 13

Answer - B

ruturaj · Answer

How can we be sure of these nos..It can be others also..How can one come with these nos

sudhir18n · Answer

it can be any other number because these are prime factors of 770

770 = 77*10 = 7*11 * 2*5

hope this helps

gmatopoeia · Answer

prime factors of 770: 2, 5, 7, 11
Therefore:
w+z=2+11=13

Answer: B

EMPOWERgmatRichC · Answer

Hi All,

We're told that the product of the integers W, X, Y and Z is 770, and that 1 < W < X < Y < Z. We're asked for the value of W + Z.

One of the great aspects of the 'math' behind factoring is that you can do the factoring in any order and you'll still get to the same result...

With 770, a few Number Properties stand out, so your first 'factor' would likely either be 2 (since 770 is EVEN), 7 (since 7 divides into 700 and 70) or 10 (since 770 ends in a 0). Let's go for the biggest option first....10

770 = (77)(10)

From here, you can further break down each of the two 'pieces'....

77 = (7)(11) 
10 = (2)(5)

770 = (2)(5)(7)(11)

Based on the given inequality 'string', we know that W is the smallest value and Z is the largest value. 2 + 11 = 13

Final Answer:  B

GMAT assassins aren't born, they're made, 
Rich

ScottTargetTestPrep · Answer

Since 770 = 2 * 5 * 7 * 11, then w = 2, x = 5, y = 7 and z = 11. Therefore, the sum of w and z is 2 + 11 = 13.

Answer: B

Pritishd · Answer

1. Prime factorization of  770  yields -  11 * 7 * 5 * 2 
2. We are given that  1 < w < x < y < z  i.e.  z = 11 ,  y = 7 ,  x = 5  and  w = 2 
3.  w + z = 2 + 11 = 13

Ans.  B

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If the product of the integers w, x, y and z is 770, and if 1 < w < x

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