Mathematics
Find the mean of 75 numbers, if the mean of 45 of them is 18 and the mean of the remaining ones is 13.
Statistics
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Answer
Mean of 45 numbers = 18
⇒ Total of 45 numbers = 45 x 18 = 810
Mean of remaining (75 - 45) 30 numbers = 13
⇒ Total of 30 numbers = 13 x 30 = 390
∴ Total of all the 75 numbers = 810 + 390 = 1,200
⇒ Mean of all the 75 numbers = = 16
Hence, the mean of 75 numbers is 16.
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