If y is 80% greater than x, than x is what % less than y?

Question

(A) 20
(B) 25
(C) 33 1/3
(D) 44 4/9
(E) 80

GSBae · Accepted Answer

y = 1.8x 
 y = \frac{9}{5}*x ; therefore  x = \frac{5}{9}*y

Therefore, x is five-ninths of y, which means x is  four-ninths less than y.  .  \frac{4}{9}  equates to 44.44 percent.

Answer: D

PatrickS · Answer

This problem looks simple enough yet i cannot understand what i am doing wrong:

y=x*\frac{180}{100}

y=x*\frac{18}{10}

y=x*\frac{9}{5}

x=y*\frac{5}{9}

x= y* 5* 0.11111

x= y* 0.555  -->  x= ~ 55.5% of y

Help...

dabral · Answer

PatrickS,

Everything you have done is correct, and your answer would be correct if they had asked x is what percent of y, which is indeed 55.55%. However, the question is asking for x is what percent less than y, which is equal to  *100 or 44.44 percent.

Dabral

PatrickS · Answer

Silly me... Thank you for clarifying

PareshGmat · Answer

y = \frac{180}{100} * x

x = \frac{100}{180} * y

Percentage  = \frac{100*100}{180} = \frac{500}{9} = 55.55

Percentage less = 100 - 55.55 = 44.45

Answer = D

NATABERI · Answer

if y=180 x=100
180-100=80

90 is 50% of y. 
80 is little less than 90 so answer D 44 4/9

EMPOWERgmatRichC · Answer

Hi All,

This is a perfect question for TESTing VALUES.

We're told that Y is 80% GREATER than X.....

Let's TEST...
X = 100
Y = 180

The question then asks "X is what percent LESS than Y?"

When a question asks for "percent greater" or "percent less", then the Percentage Change Formula is required.

Percentage Change = (New - Old)/Old = Difference/Original

Here, the "new" number is 100 and the "old" number is 180 (you could also say that the difference is 80 and the 'original' number is 180).

Depending on which version of the formula you use, your answer might look a little different, but the end "meaning" is the same....

(100 - 180)/180 = -80/180 = -8/18 = -4/9 = -44.4444% The 'minus' sign means "less"

OR

80/180 = 8/18 = 4/9 = 44.444%

Either way, the "meaning" is the same: X is 44.4444% less than Y.

Final Answer:  D

GMAT assassins aren't born, they're made,
Rich

dream21 · Answer

Since we need to find X percent  less  than Y

y-x/y = (1.8x-x)/1.8x = 44(4/9)

Ans : D

PareshGmat · Answer

Answer = D. 44 4/9

Say x = 100, then y = 180

Percent less  = 100*\frac{80}{180} = 44 \frac{4}{9}

Bunuel · Answer

MAGOOSH OFFICIAL SOLUTION: yis80percentgreaterthanx_text.PNG

OptimusPrepJanielle · Answer

Let x = 100 So y = 180 We want percentage change. So, (100-180)/180 = -44.44% = 44 4/9% lesser tha y. Hence option (D). -- Optimus Prep's GMAT On Demand course for only $299 covers all verbal and quant. concepts in detail. Visit the following link to get your 7 days free trial account: https://www.optimus-prep.com/gmat-on-demand-course

Harish Yannam · Answer

y=180/100 x

x=5/9 y

y-5/9y = 4/9 y

4/9 y *100 = 44 4/9

therefore option d.

JeffTargetTestPrep · Answer

We can create the following equation:

y = 1.8x

Thus:

(x - y)/y * 100 = (x - 1.8x)/1.8x * 100 = -0.8x/1.8x * 100 = -8/18 * 100 = -4/9 * 100 = -44 4/9

We see that x is 44 4/9 percent less than y.

Answer: D

MathRevolution · Answer

Let x be 100. Therefore, y = 180

=>  \frac{(y - x) }{ y}  * 100 =  \frac{(180 - 100)}{ 180}  * 100

=>  \frac{80}{180}  * 100 = 44.44

Answer D

DeadScout · Answer

You are counting X as a percentage of Y. The question asks what percentage of Y is the difference between Y and X (in simple terms)

If y is 80% greater than x, than x is what % less than y?

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GMAT Problem Solving (PS) Questions

If y is 80% greater than x, than x is what % less than y?

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