GMAT
Exam
a, b, and c are positive integers. If a, b, and c are assembled into the six-digit number abcabc,
which one of the following must be a factor of abcabc?
(A) 16
(B) 13
(C) 5
(D) 3
(E) none of the above
Read Solution (Total 3)
-
- The number is abc*1001. 1001 = 7*11*13. So, abcabc is divisible by (B)13
- 15 years agoHelpfull: Yes(4) No(6)
- abcabc = 100000a + 10000b + 1000c + 100a + 10b + c
= 100100a + 10010b + 1001c
=1001(100a + 10b + c)
The above expression has 3 as a factor (1001 is divisible by 3).
Hence, 3 should be the answer. - 10 years agoHelpfull: Yes(3) No(1)
- 13
- 15 years agoHelpfull: Yes(2) No(2)
GMAT Other Question