Product of Integers

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Re: Product of Integers

by Brent@GMATPrepNow » Fri Mar 06, 2009 10:17 am
Marisa wrote:If the integers w,x,y,z is 770 and if 1<w<x<y<z. What is z?
This requires us to use prime factorization.
770 = 2x5x7x11
If 1<w<x<y<z then:
w=2
x=5
y=7
z=11
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Re: Product of Integers

by bluementor » Fri Mar 06, 2009 10:20 am
Marisa wrote:If the integers w,x,y,z is 770 and if 1<w<x<y<z. What is z?
I believe the question should read:

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

The answer to this question would be:

w*x*y*z = 770
w*x*y*z = 10 x 77
w*x*y*z = 2x5 x 7x11

Since z is the largest factor, z must be 11.

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by Marisa » Fri Mar 06, 2009 10:23 am
Thank you. How do you know when to do prime factorization? I cannot find another sample question which requires prime factorization. Thank you.