The distributions X and Y with Total number of observations 36 and 64, and mean 4 and 3 respectively are combined. What is the mean of the resulting distribution X + Y?
According to the question,
⇒ X = 36 × 4 = 144 and Y = 64 × 3 = 192
We have, X = 144 and Y = 192
Mean of distribution (X + Y = 144 + 192 = ) 336 is,
Mean = 336/(36 + 64) = 336/100 = 3.36
Hence, mean = 3.36
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