Problem solving

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Problem solving

by BTGmoderatorRO » Sun Sep 10, 2017 9:37 am
Which of the following option is correct when (6(x^3)(y^3))^4 + (4x^4)^3 *(y^6) is divided by (2* x^4* y^6) ^2, if xy≠0?

A. (2^2)(3^4)(x^4)+(2^4)(x^4) y^(-6)

B. (3^2)(x^4)+(4^2)(x^4) y^(-6)

C. (2^10)(x^4)y + (2^4)(x^4)(y^4)

D. (2^3)(3^4)(x^4) + (4^3)(x^12)(y^16)

E. (3^2)(x^4) + (4^3)(x^12)(y^16)

OA is A

I have been having a nightmare with this question for some days now. Every options seem confusing. Should i stick with option E?

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by Brent@GMATPrepNow » Sun Sep 10, 2017 10:22 am
Roland2rule wrote:Which of the following option is correct when (6(x^3)(y^3))^4 + (4x^4)^3 *(y^6) is divided by (2* x^4* y^6) ^2, if xy≠0?

A. (2^2)(3^4)(x^4)+(2^4)(x^4) y^(-6)

B. (3^2)(x^4)+(4^2)(x^4) y^(-6)

C. (2^10)(x^4)y + (2^4)(x^4)(y^4)

D. (2^3)(3^4)(x^4) + (4^3)(x^12)(y^16)

E. (3^2)(x^4) + (4^3)(x^12)(y^16)

OA is A

I have been having a nightmare with this question for some days now. Every options seem confusing. Should i stick with option E?
We can just focus on the colored parts of this expression

6^4 = [(2)(3)]^4
= (2^4)(3^4)


So, we get (2^4)(3^4)/(2^2) = (2^2)(3^4)

Now look for a match for the corresponding term in the answer choices....

A. (2^2)(3^4)(x^4)+(2^4)(x^4) y^(-6) ...a MATCH

B. (3^2)(x^4)+(4^2)(x^4) y^(-6)...no match - ELIMINATE

C. (2^10)(x^4)y + (2^4)(x^4)(y^4)...no match - ELIMINATE

D. (2^3)(3^4)(x^4) + (4^3)(x^12)(y^16)...no match - ELIMINATE

E. (3^2)(x^4) + (4^3)(x^12)(y^16)...no match - ELIMINATE

Answer: A

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
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