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The arithmetic of 12 observations is 15...

The arithmetic of 12 observations is 15. If two observations 20 and 25 are removed then the arithmetic mean of remaining observations is

A

14.5

B

13.5

C

12.5

D

13

Text Solution

Verified by Experts

The correct Answer is:
`C`

`"AM" = ("Sum of all observations")/("Total number of observations")`
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PEARSON IIT JEE FOUNDATION-STATISTICS-LEVEL-1
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  3. The mean of a set of observation is a. If each observation is multipli...

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  4. The mean deviation of first 8 composite numbers is .

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  5. Find the mode of the following discrete series. {:(x,f," "x,f...

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  6. The the highest score of certain data exceeds its lowest score by 16 a...

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  7. Find the mean deviation (approximately) about the mode for the followi...

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  9. The arithmetic of 12 observations is 15. If two observations 20 and ...

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  10. The arithmetic mean and mode of a data are 24 and 12 respectively, the...

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  11. The inter-quartile range of the observations 3, 5, 9, 11, 13, 18, 23, ...

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  12. Find the mean deviation from the mode for the following ungrouped data...

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  13. If the mean of the following frequency distribution is 5, then b = ...

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  14. The mean deviation of (a+b)/(2) "and" (a-b)/(2) (where a and b gt 0) i...

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  15. If the mean of x + 2, 2x + 3, 3x + 4 and 4x + 5 is x + 2, then find th...

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  16. The range of 15, 14, x, 25, 30, 35 is 23. Find the least possible valu...

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  17. Find the median of the following data. {:("Class Interval",f),(" "0...

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  18. In the following table, pass percentage of three schools from the year...

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  19. The Median of the following discrete series is {:(x(i),3,6,5,8,12,...

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  20. Which of the following does not change for the observations 23, 50, 27...

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