Q. P scored 40 marks more than Q in an examination. If Q scored 10% less marks than P, then how much did Q score.
(a) 360
(b) 380
(c) 400
(d) 420
Correct Answer: (a) 360
Question from UPSC Prelims 2021 CSAT Paper
Explanation :
Examination Score Analysis of P & Q
Let’s say P scored x marks in the examination. Since P scored 40 marks more than Q, Q scored x-40 marks.
According to the question, Q also scored 10% less marks than P. So we can write an equation to represent this: (x-40) = 0.9x.
Solving this equation for x, we get: x – 40 = 0.9x
x – 0.9x = 40 ; 0.1x = 40; x = 400
So P scored 400 marks in the examination and Q scored x-40 = 400-40 = 360 marks.
