What is the value of (2^{2020} + 2^{2018}) / (2^{2020}-2^{20

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[GMAT math practice question]

What is the value of (2^{2020} + 2^{2018}) / (2^{2020}-2^{2018})?

A. 3/5
B. 5/3
C. 2^{2018}
D. 2^{2019}
E. 2^{2020}

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by GMATGuruNY » Fri Feb 15, 2019 4:55 am
Max@Math Revolution wrote:[GMAT math practice question]

What is the value of (2^{2020} + 2^{2018}) / (2^{2020}-2^{2018})?

A. 3/5
B. 5/3
C. 2^{2018}
D. 2^{2019}
E. 2^{2020}
(2²�²� + 2²�¹�)/(2²�²� - 2²�¹�)

= (2²�¹�)(2² + 1) / (2²�¹�)(2² - 1)

= 5/3.

The correct answer is B.
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by Max@Math Revolution » Sun Feb 17, 2019 5:17 pm
=>

(2^{2020} + 2^{2018}) / (2^{2020}-2^{2018})
= (2^22^{2018} + 2^{2018}) / (2^22^{2018}-2^{2018})
= (2^{2018})(2^2+1) / (2^{2018})(2^2-1) = (2^2+1) / (2^2-1)
= 5/3

Therefore, the answer is B.
Answer: B