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In a class of 50 students, 10 have failed and their average marks are 28. The total marks obtained by the entire class on 2800. The average marks of those who have passed, are

A) 43
B) 53
C) 63
D) 70

Correct Answer:



C) 63

Description for Correct answer:
Total marks of 10 failed students = 28 x 10 = 280

and total marks of 50 students = 2800

Therefore, Total marks of 40 passed students . 5 = 2800 - 280 = 2520

Therefore, Average marks of 40 passed students = \( \Large \frac{2520}{40} = 63 \)

Part of solved Statistics questions and answers : >> Elementary Mathematics >> Statistics

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Similar Questions

1). The mean of n observations is \( \Large \overline{x} \). If one observation \( \Large x_{n+1} \) is added, then the mean remains same. The value of \( \Large x_{n+1} \) is:

A). 0

B). 1

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2). In a class of 100 students, the average amount of pocket money is Rs.35 per student. If the average is Rs.25 for girls and Rs.50 for boys, then the number of girls in the class is

A). 20

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A). \( \Large \frac{2^{n}}{n} \)

B). \( \Large \frac{2^{n}}{n+1} \)

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A). \( \Large |\frac{c}{a}|\sigma \)

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