Question

If 3 students averaged 68 on a test and 4 students averaged 75, what is the average of all 7 students

A=70
B=71
C=72
D=73
E=74

Answer 1

Option C

Explanation:

Total score for 3 students will be given by the product of average and frequency.

Total score for three students will then be 68*3=204

Similarly, for 4 students, their total score will also be given by

4*75=300

Adding the total score for the two groups

300+204=504

To get the average of all the 7 students, we divide the total score by frequency hence 504/7=72

Therefore, option C is correct