Q12
ArithmeticAverages & Ages
The average marks obtained by 9 students was calculated to be 65. Later on it was found that the marks of one student was wrongly read as 76 instead of 67. The correct average is:
- a.56
- b.64
- c.66
- d.74
Answer: (B) 64
The wrong total was 9 × 65 = 585, which is 76 − 67 = 9 too high. The correct total is 576, and 576 ÷ 9 = 64. 66 would follow from adding the error instead of subtracting it.