Question

A partial sum of an arithmetic sequence is given. Find the sum.

Answer 1

Answer:

72.3

Step-by-step explanation:

Given that:

The arithmetic sequence:

$\sum \limits ^{14}_{k=0} (3 + 0.26k)$

The first term of the sequence $a_0$ = 3 since k = 0

i.e (3 + 0.26(0)) = 3

The last term of the sequence $a_{14}$ = 6.64

i.e (3+ 0.26(14)

= (3 + 3.64)

= 6.64

Total no of terms = 15 i.e from 0 to 14

∴

The partial sum of the arithmetic sequence = $\dfrac{Total \ no \ of \ terms }{2} \times (a_o+a_{15})}$

$=\dfrac{15 }{2} \times (3+6.64)}$

= 72.3