36. Of the four numbers, the first is twice the second, the second is one-third of the third and the third is 5 times the fourth. The average of the numbers is 24.75. The largest of these numbers is :
A.9
B.25
C.30
D.None of these

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37. Of the four, whose average is 60, the first is one-fourth of the sum of the last three. The first number is :
A.15
B.45
C.48
D.60.25

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38. Of the three numbers, the first is twice the second and the second is twice the third. The average of the reciprocal of the numbers is 7/72. The numbers are :
A.16,8,4
B.20,10,5
C.24,12,6
D.36,18,9

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39. Of the three numbers, the average of first and the second is greater than the average of the second and the third by 15. What is the difference between the first and the third of the three numbers?
A.15
B.45
C.Data inadequate
D.None of these

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40. If the arithmetic mean of seventy-five numbers is calculated, it is 35. If each number is increased by 5, then mean of new numbers is :
A.30
B.40
C.70
D.90

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41. The average of ten numbers is 7. If each number is mu1tp1ied by 12, then th average of the new set of numbers is :
A.7
B.19
C.82
D.84

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42. Average of ten positive numbers is x. If each number is increased by 10%, then x:
A.remains unchanged
B.may decrease
C.may increase
D.is increased by 10%

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