In an examination, the maximum possible score is while the pass mark is of . A candidate obtains marks, but falls short of the pass mark by . Which one of the following is then correct?
In an examination, the maximum possible score is while the pass mark is of . A candidate obtains marks, but falls short of the pass mark by . Which one of the following is then correct?
Solution
Let's break down what we know:
Maximum possible score: N
Pass mark: 45% of N
Candidate's score: 36 marks
Candidate falls short of pass mark by: 68%
The key insight here is understanding what "falls short by 68%" actually means.
When we say someone "falls short by 68%", it means they achieved only (100% - 68%) = 32% of the required pass mark.
Think of it this way: If you need 100 marks to pass, and you fall short by 68%, you got only 32 marks.
So our candidate achieved 32% of the pass mark.
Since the candidate got 32% of the pass mark:
Pass mark = 45% of N = 0.45N
Candidate's achievement = 32% of pass mark
= 32% of (0.45N)
= 0.32 × 0.45N
= 0.144N
But we know the candidate scored 36 marks, so:
0.144N = 36
0.144N = 36
Therefore, N = 250
When a problem states someone "falls short by X%", remember:
They achieved (100% - X%) of the target
Set up your equation using this percentage of the target value
This approach works for any similar percentage shortage problems!