Question: The number of prime factors of`(6)^(10) xx (7)^(17) xx (55)^(27)` is :
A
54
B
64
C
81
D
91
Note: `(6)^(10) xx (7)^(17) xx (55)^(27)`
`= 2^(10) xx 3^(10) xx 7^(17) xx 5^(27) xx 11^(27)`
:. The total number of prime factors
`= (10 + 10 + 17 + 27 + 27) = 91`
Question: The number of prime factors in` (1/6)^(12) xx (8)^(25) xx (3/4)^(15)` is :
A
33
B
37
C
52
D
None
Note: `(1/6)^(12) xx (8)^(25) xx (3/4)^(15)`
`= 1/(2^(12) xx 3^(12)) xx (2^3)^(25) xx 3^(15)/(2^15 xx 2^15)`
`= (2^75 xx 3^15)/(2^42 xx 3^12)`
`= 2^33 xx 3^3`
:. Total number of prime factors
`= (33 + 3) = 36`
Question: A number when divided by 32 leaves the remainder 29. This number when divided by 8 will leave the remainder :
A
3
B
5
C
7
D
29
Note: Let the given number be x. The when divided by 32. suppose gives the quotient k. Then,
`x = 32 k + 29 = 8 xx (4 k + 3) + 5`
Thus, when x is divided by 8. it gives `(4 k + 3)` as quotient and 5 as remainder.