Find the indicated nth partial sum of the arithmetic sequence. 2.5, 3.8, 5.1, 6.4, ..., n = 100
A) 12,505
B) 6815
C) 6685
D) 6683.8
E) 6686.2

Question

Quizplus · Accepted Answer

The sequence is arithmetic with the first term a = 2.5 and common difference d = 1.3. The nth partial sum of an arithmetic sequence is given by S_n = n/2 * (2a + (n-1)d). Substituting n = 100, a = 2.5, and d = 1.3, we get S_100 = 100/2 * (2*2.5 + 99*1.3) = 6685.

Find the Indicated Nth Partial Sum of the Arithmetic Sequence