In an exam, total marks gained by four students were 720.5. A got 10% less than B, B got 30% more than C and C got 25% less than D. If A got 175.5 marks, how much marks did D get in the examination?
1. 200
2. 150
3. 175
4. 250
1. 200
2. 150
3. 175
4. 250
Correct Answer – Option 1 : 200
Given:
Total marks = 720.5
A got 10% less than B, B got 30% more than C and C got 25% less than D.
A got marks = 175.5
Calculation:
Marks obtained by given person in terms of another person = Marks obtained by another person +/- markspercentage by which another person obtains more/less marks than the given person
Calculation:
Let the marks obtained by D be x.
C got 25% less than D.
C = x – 25% of x
⇒ 75% of x = 0.75x
B got 30% more than C.
B = 0.75x + 30%of 0.75x
⇒ 0.75x + 0.225x
⇒ 0.975x
A got 10% less than B.
A = 0.975x – 10% of 0.975x
⇒ 0.975x – 0.10 × 0.975x
⇒ 0.8775x
A got marks = 175.5
⇒ 0.8775x = 175.5
⇒ x = 175.5/0.8775
⇒ x = 200 marks
∴ D obtained 200 marks.