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by vinviper1 » Wed May 14, 2008 8:02 am
Peter got 30% of the maximum marks in an examination and failed by 10 marks. However, Paul who took the same examination got 40% of the total marks and got 15 marks more than the passing marks. What was the passing marks in the examination?

A. 35
B. 250
C. 75
D. 85
E. 90
Source: — Problem Solving |

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by aatech » Wed May 14, 2008 8:20 am
Suppose the max marks is x

Peter got 30% of x = 3x/10

Paul got 40% of x = 4x/10

Passing mark = [3x/10] + 10 = [4x/10]-15
Solve to get x = 250

Passing marks = [4x/10]-15 = 85

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by Mclaughlin » Wed May 14, 2008 8:30 am
In the above answer why did you divide 3x and 4x by 10?

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by aatech » Wed May 14, 2008 8:42 am
30% of x => [30/100]*x => [3/10]*x = 3x/10