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In a class of 100 students there are 70 ...

In a class of 100 students there are 70 boys whose average marks in subject are 75. If the average marks of the complete class are 72, then the average marks of the girls

A

73

B

65

C

68

D

74

Text Solution

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The correct Answer is:
B
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PATHFINDER-STATISTICS-QUESTION BANK
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  7. Find the mean deviation about the median of the data : 34, 23, 46, 37,...

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  8. Find the mean if the coefficient of variation is 5% and variance is 4.

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  9. If co-efficient of variation = 45% and mean = 24. Find the standard De...

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  10. Two variables x and y are related by y = 2-3x If the S.D of x be 1.5 t...

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  11. The variance of first n natural numbers is 44. Find the value of n.

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  12. Find the range for the following frequency distribution :

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  14. If the SD of the first numbers even integers be sqrt40, then find numb...

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