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
14 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.
9 years agoHelpfull: Yes(3) No(1)
13
14 years agoHelpfull: Yes(2) No(2)

GMAT Other Question

a, b, and c are integers and a < b < c. S is the set of all integers from a to b, inclusive. Q is the
set of all integers from b to c, inclusive. The median of set S is (3/4)b. The median of set Q is
(7/8)c. If R is the set of all integers from a to c, inclusive, what fraction of c is the median of set
R?
(A) 3/8
(B) 1/2
(C) 11/16
(D) 5/7
(E) 3/4
A certain club has exactly 5 new members at the end of its first week. Every subsequent
week, each of the previous week's new members (and only these members) brings exactly x new
members into the club. If y is the number of new members brought into the club during the
twelfth week, which of the following could be y?
(A) 3
(B) 6
(C) 4
(D) 8
(E) 5