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Question
The distribution 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?
Solution
According to the question,
4 =`X/36 and 3 = Y/64`
โน ๐ = 4×36 ๐๐๐ ๐ = 3×64
โน ๐ = 144 ๐๐๐ ๐ = 192
๐๐๐ค, ๐ + ๐ = 144 + 192 = 336
And total number of observations = 36 + 64 = 100
Thus, mean =`336/100= 3.36.`
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