Question

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6.6 The mean of 37 observations is 70. If the mean of the first 18 observations is 42 and that of the last
18 observations is 40, what will be the 19th observation?
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Answer 1

Step-by-step explanation:

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Answer 2

Answer:

19th observation =1114

Step-by-step explanation:

Given:-

The mean of 37 observations is 70. If the mean of the first 18 observations is 42 and that of the last

The mean of 37 observations is 70. If the mean of the first 18 observations is 42 and that of the last18 observations is 40.

To find:-

what will be the 19th observation?

Solution:-

The mean of 37 observations=70

Sum of 37 observations=70×37=2590

And,

Mean of first 18 observations=42

Sum of first 18 observations=42×18=756

Mean of last 18 observations=40

Sum of last 18 observations=40×18=720

Sum of 37 observations =

Sum of first 18 observations+19th observation+Sum of last 18 observations

=>2590=756+19th observation+720

=>2590=1476+19th observation

=>19th observation=2590-1476=1114

Answer:-

19th observation =1114

Used concept:-

Mean=Sum of all observations/Nom of all observations