78. In a division sum, the remainder is 0. A student mistook the divisor by 12 instead of 21 and obtained 35 as quotient. What is the correct quotient ?
A.0
B.12
C.13
D.20

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79. The sum of the two numbers is 12 and their product is 35. What is the sum of the reciprocals of these numbers ?
A.12/35
B.1/35
C.35/8
D.7/32

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80. If 60 % of 3/5 of a number is 36, then the number is :
A.80
B.100
C.75
D.90

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81. The difference between a positive proper fraction and its reciprocal is 9/20. The fraction is :
A.3/5
B.3/10
C.4/5
D.5/4

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82. On dividing 2272 as well as 875 by 3-digit number N, we get the same remainder. The sum of the digit of N is :
A.10
B.11
C.12
D.13

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83. On multiplying a number by 7, the product is a number each of whose digits is 3. The smallest such number is :
A.47619
B.47719
C.48619
D.47649

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84. The difference of the squares of two consecutive even integers is divisible by which of the following integers ?
A.3
B.4
C.6
D.7

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