Data sufficiency

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Data sufficiency

by Nury Yeashfi » Wed Jun 19, 2019 12:10 pm
If y=1+1/x where x>1, then y could equal to which of the following?
a. 1/5
b. 5/8
c. 9/7
d. 15.11
e. 8/7

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by [email protected] » Wed Jun 19, 2019 12:47 pm
Nury Yeashfi wrote:If y = 1 + 1/x where x >1 , then y could equal to which of the following?
a. 1/5
b. 5/8
c. 9/7
d. 15.11
e. 8/7
Take: y = 1 + 1/x
Rewrite as: y = x/x + 1/x
Simplify: y = (x + 1)/x

So, we're looking for an answer choice that can be expressed as a fraction in which the numerator is 1 greater than the denominator.
Answer: E

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by Ian Stewart » Fri Jun 28, 2019 6:52 am
If x > 1, then 1/x is between 0 and 1. So 1 + (1/x) will be between 1 and 2, and answers C and E are both possible (for C, x = 7/2, and for E, x = 7). If there's a typo in D, and instead it's meant to read "15/11", then D is also possible (x = 11/4). It's only if the question tells you x is an integer that E becomes the lone correct answer among the choices, but the question doesn't tell us that.

So the question has two or three right answers, which can't happen on the GMAT - where is it from?
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by oabpyhfv » Sat Jul 20, 2019 12:25 am
In the figure below AB=BC=CD. If the area of the Traingle CDE is 42,what is the area of the triangle ADG?
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similar triangle sides of CDE are 1/3 of the Side of ADG.
9 X Area of triangle CDE = area of Triangle ADG

Area of Triangle ADG =9 X 42

Area of Triangle ADG =378