The average mark of student in 4 subjects is 75. If the student obtained 80 marks in the fifth subject, then the new average is-

Answer: Option B

Sum of marks in 4 subjects
= 75 × 4
= 300
Sum of marks in 5 subjects
= 300 + 80
= 380
∴ New average
= $$\frac{380}{5}$$
= 76