The sequence a1, a2, a3, a4, a5 is such that an = an-1 + 5. For 2<=n <=5. If a5 = 31, what is the value of a1?
(A) 1
(B) 6
(C) 11
(D) 16
(E) 2
(A) 1
(B) 6
(C) 11
(D) 16
(E) 2
Each number in the sequence is 5 more than the previous, so we can quickly work backwards to determine the answer...Eternalhope wrote:The sequence a1, a2, a3, a4, a5 is such that an = an-1 + 5. For 2<=n <=5. If a5 = 31, what is the value of a1?
(A) 1
(B) 6
(C) 11
(D) 16
(E) 2
a5=31
a4=26
a3=21
a2=16
a1=11
C
