Correct Answer - Option 3 : 77

**Given :**

In an exam B scored 50% more marks than A and 40% fewer marks than C, D scored 18% more marks than B.

**Calculations :**

Let the marks of A in the exam be 100

B's marks = 100 + 50% of 100 (B scored 50% more than A)

⇒ 150

It is given B scored 40% fewer marks than C that means B scored 60% of C's score.

B's marks = 60% of C's score

60% of C's score = 150

C's score = 250 marks

D's score = 150 + 18% of 150 (D scored 18% more than B)

⇒ 150 + 27

⇒ 177 marks

D score = 177 and A score = 100

Required per cent = (177 - 100)/(100) × 100

⇒ 77%

**∴ Option 3 will be the correct choice.**