15. Twenty times a positive integer is less than its square by 96. What is the integer ?
A.20
B.24
C.30
D.Cannot be determined

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16. Thrice the square of a natural number decreased by 4 times the number is equal to 50 more than the number. The number is :
A.4
B.5
C.6
D.10

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17. The sum of a number and its reciprocal is one-eighth of 34. What is the produt of the number and its square root?
A.8
B.27
C.32
D.None of these

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18. Two-third of a positive number and 25/216 of its reciprocal are equal. The number is:
A.5/12
B.12/5
C.25/144
D.144/25

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19. Find a positive number which when increased by 17 is equal to 60 times the reciprocal of the number.
A.3
B.10
C.17
D.20

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20. A positive number when decreased by 4 is equal to 21 times the reciprocal of the number. The number is :
A.3
B.5
C.7
D.9

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21. The product of two natural numbers is 17. Then, the sum of the reciprocals of their squares is :
A.
B.
C.
D.289

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