In an exam, A gets 25% more marks than B, B gets 10% less marks than C and C gets 25% more marks than D. If D gets 320 marks out of 500 then A's marks are?
Answer & explanation
Correct answer: option 2
25% = \(\frac{1}{4}\), 25% more = \(\frac{5}{4}\)
10% = \(\frac{1}{10}\), 10% less = \(\frac{9}{10}\)
D's marks = 320
C's marks = D's marks × \(\frac{5}{4}\) = 320 × \(\frac{5}{4}\)
B's marks = C's marks × \(\frac{9}{10}\) = 320 × \(\frac{5}{4}\) × \(\frac{9}{10}\)
A's marks = B's marks × \(\frac{5}{4}\) = 320 × \(\frac{5}{4}\) × \(\frac{9}{10}\) × \(\frac{5}{4}\) = 450