Statisticsmedium · Past Paper
The mean marks of 20 students is 45 and the mean marks of another 30 students is 50. Find the combined mean.
A47.5
B48
C46
D49
✓ Correct Answer: B — 48
Combined Mean = (n1*m1 + n2*m2) / (n1 + n2) = (20*45 + 30*50) / 50 = (900 + 1500) / 50 = 2400 / 50 = 48.
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