If Musa scored 75 in biology instead of 57, his average mark in four subjects would have been 60. What was his total mark?
-
A.
282 -
B.
240 -
C.
222 -
D.
210
Correct Answer: Option C
Explanation
Let x represent Musa’s total mark when he scores 57 in biology and Let Y represent Musa’s total mark when he now scored 75 in biology, if he scored 75 in biology his new total mark will be (frac{Y}{4}) = 60, y = 4 x 60 = 240
To get his total mark when he scored 57, subtract 57 from 75 to give 18, then subtract this 18 from the new total mark(ie. 240)
= 240 – 18
= 222