pp-T1-DS170

[Huang Hsin-Yi]

170.
If n and t are positive integers, what is the greatest prime factor of the product nt ?

(1) The greatest common factor of n and t is 5.

(2) The least common multiple of n and t is 105.

Ans:B

[mupeane]

170.
If n and t are positive integers, what is the greatest prime factor of the product nt ?

(1) The greatest common factor of n and t is 5.

(2) The least common multiple of n and t is 105.

Ans:B

(1)最大共同因數是5，所以n跟t可能各有其它質因數
(2)最小公倍數105=5x3x7, 所以nt的最大質因數是7

[Huang Hsin-Yi]

謝謝mupeane大大
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