Statisticshard · Past Paper
The mean age of 30 students is 15 years. If the teacher's age is included, the mean increases by 1 year. Teacher's age is:
A45
B31
C46
D16
✓ Correct Answer: C — 46
Total age = 30*15 = 450. New total = 31*16 = 496. Teacher = 496 - 450 = 46.
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