For a,b,d are the positive integers, and d|a means that "a is divisible by d", if d|ab, which of the following must be true?
A. d|a
B. d|b
C. d|2ab
D. d|(a+b)
E. d|(a-b)
* A solution will be posted in two days.
For a,b,d are the positive integers, and d|a means that “a
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For a,b,d are the positive integers, and d|a means that "a is divisible by d", if d|ab, which of the following must be true?
A. d|a
B. d|b
C. d|2ab
D. d|(a+b)
E. d|(a-b)
--> d|ab is ab=dk(k=integer) and also 2ab=2dk can be divided by d.
Therefore, the answer is C.
A. d|a
B. d|b
C. d|2ab
D. d|(a+b)
E. d|(a-b)
--> d|ab is ab=dk(k=integer) and also 2ab=2dk can be divided by d.
Therefore, the answer is C.
Math Revolution
The World's Most "Complete" GMAT Math Course!
Score an excellent Q49-51 just like 70% of our students.
[Free] Full on-demand course (7 days) - 100 hours of video lessons, 490 lesson topics, and 2,000 questions.
[Course] Starting $79 for on-demand and $60 for tutoring per hour and $390 only for Live Online.
Email to : [email protected]