If y 0 and x is y percent of y, then, in terms of y, y is what

Question

If y > 0 and x is y percent of y, then, in terms of y, y is what percent of x ?

A -  \frac{1}{y}

B -  \frac{1}{100y}

C -  100y

D -  \frac{10000}{y}

E -  \frac{1}{10000y}

I searched but i could only find similar questions, not this exact one. If its a repost, please feel free to merge.

akshayk · Answer

We can solve it 2 ways, either by plugging values, or doing algebra.

x =  \frac{y^2}{100}

y =  \frac{a}{100} *x
=> a =  \frac{y*100}{x} 
=> a =  \frac{10000}{y}

Answer is D.

Alternatively.

Let y = 100
100% of 100 = 100 = x
100 = a% of 100
=> a = 100
So we can plug values of y in the given options below to see which one works.

A -  \frac{1}{100}  - NO
B - Even Smaller - NO
C - 100*100 - NO
D -  \frac{10000}{100}  = 100 - YES
E - NO its way too small.

D is the answer.

GMATinsight · Answer

x is y percent of y

i.e. x = (y/100)*y = y^2/100

y is what percent of x
let y is a percent of x
i.e. y = (a/100)*x
i.e. a = 100y/x = 100y/  = 10000/y

Answer: Option D

Bunuel · Answer

This is a copy of the following OG question: https://gmatclub.com/forum/if-m-0-and-x ... 03387.html

mohshu · Answer

x is y percent of y
x = (y/100)*y = y^2/100

let y is a percent of x
y = (a/100)*x
a = 100y/x = 100y/  = 10000/y

ans D

sarbjeetsingh777 · Answer

it is given that x is y percent of y, so lets assume x=25 and y=50. So we get, 25(i.e. x) is 50%(i.e. y%) of 50(i.e. y). 
Now clearly y is 200% of x. Put the values of x and y in options and select the one which gives 200 as answer. Only option D will fit. 
Hence D

roadrunner · Answer

x = y%*y
=y/100 * y (here y/100 is the multiplier)
y = (100/y) * x ( where, 100/y is the multiplier)
y = (100/y)*x * 100 (convert to percent unit)
y = (10000/y) % of x

generis · Answer

Choosing numbers is probably the easiest approach. Ordinarily, avoid using numbers that are similar to those in the answer choices.

Let y = 20

x is y percent of y
x is 20% of 20

x = .2 * 20
x = 4

y is what percent of x?

\frac{y}{x}  * 100 =

\frac{20}{4}  = 5 * 100 = 500%

We're looking for the answer that yields 500 when y = 20.

A)  \frac{1}{y}=\frac{1}{20}=.05  
Much too small. We need 500. Eliminate.

B)  \frac{1}{100y}=\frac{1}{100(20)}=\frac{1}{2,000}= 
Even smaller than A. (B =.0005). Eliminate

E)  \frac{1}{10000y}=  Even smaller than B. 
Not even close to 500. Eliminate

(Typically, scan answers first and eliminate A, B, and E immediately. The fractions have y = 20 in the denominators and 1 on top. Those answers are tiny regardless and tiny when compared to 500.)

C. 100y: too large. 
(20 * 100) = 2,000. Eliminate

D.  \frac{10,000}{y}=\frac{10,000}{20}  = 500. Correct.

Answer D

Kinshook · Answer

Given:
1. y > 0
2. x is y percent of y

Asked: In terms of y, y is what percent of x ?

x = y% y = y*y / 100
y = 100x/y = (10000/y)% x

IMO D

bumpbot · Answer

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If y > 0 and x is y percent of y, then, in terms of y, y is what

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