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The mean of 40 observations was 160. It ...

The mean of 40 observations was 160. It was detected on rechecking that the value of 165 was wrongly copied as 125 for computation of mean. Find the correct mean.

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Mean`=160`
Number of terms `(n)=40`
Mean`=(sumx_i)/n`
160`=(sumx_i)/40`
`sumx_i=160xx40`
`sumx_i=6400`
Now, the correct mean will be:
Mean`=(6400-125+165)/40`
Mean`=6440/40`
Mean`=161`
Hecne, the correct mean is `161`.
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RD SHARMA-MEASURES OF CENTRAL TENDENCY-All Questions
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  11. Find the arithmetic means of first 6 natural numbers.

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  12. Find the arithmetic mean of first ten odd natural numbers.

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  15. Find the sum of the deviations of the variate values 3, 4, 6, 8, 14 ...

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