The difference between the value of a number increased by 12.5% and th

Question

The difference between the value of a number increased by 12.5% and the value of the original number decreased by 25% is 30. What is the original number?

A. 60
B. 80
C. 40
D. 120
E. 160

Kurtosis · Accepted Answer

(1 + 1/8)x - (1 - 1/4)x = 30
(9/8)x - (3/4)x = 30
x = 80

Answer: B

Abhishek009 · Answer

12.5 % =  \frac{1}{8} 
 25 % =  \frac{1}{4}

Let the original number be 8

Value of the number is 9

Value of the number is 6

So, 9 - 6 represents 30

Or, 3 represents 30

Or, 1 represents 10

Or, 8 represents 80

So, The original number is 80, answer will be (B) 80

ydmuley · Answer

The difference between the value of a number increased by 12.5% and the value of the original number decreased by 25% is 30. What is the original number?

Let the original number be x

x + 0.125x - (x - 0.25x) = 30

1.125x - 0.750x = 30

0.375x = 30

x = \frac{30}{0.375}

x = 80

Hence, Answer is B

nks2611 · Answer

let's original value be X

now go through the stem the diif b/t x(1+1/8) - x(1-1/4) = 30
 x( 9-6/8) = 30
 x = 30*8/3 
 x = 80
hence B

OptimusPrepJanielle · Answer

Assume the number to be 100x
Given, 112.5x - 75x = 30

37.5x = 30
x = 30/37.5

Number = 100*30/37.5 = 80

Correct Option: B

matthewsmith_89 · Answer

1.125x - 0.75x = 30
0.375x = 30
375/1000x = 30
375x = 30000
x = 80

Answer B is the correct answer.

elegantm · Answer

Would like to share a different approach to solve the problem.....

I know 12.5% means =  \frac{1}{8} 
Let's assume original number is 8x
Increase of 12.5% of 8x =  \frac{1}{8}  . 8x = x
(I hope now everyone why i choose original number 8x)
Decrease of 25% of 8x =  \frac{1}{4}  . 8x = 2x

Total change in Increase & Decrease 
3x = 30
So x = 10

Thus Original Number = 80

Hence Answer B

ScottTargetTestPrep · Answer

We can let x = the number.

We can create the following equation and determine x:

1.125x - 0.75x = 30

0.375x = 30

x = 30/0.375

x = 80

Answer: B

Paras96 · Answer

The difference between the value of a number increased by 12.5% and the value of the original number decreased by 25% is 30. What is the original number?

Let the original number be 1000x,
The value of the number increased by 12.5% = 1125x
The value of the number decreased by 25% = 750x

Difference = 1125x-750x=375x=30
=> x=30/375=10/125

Therefore, the original number = 1000x = 1000*10/125 = 80

Hence B

bumpbot · Answer

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