To find the sum of the arithmetic series, we first need to find the number of terms in the series. The first term is -5 and the last term is 65, with a common difference of 5.
The formula for finding the nth term of an arithmetic series is:
an = a1 + (n-1)d
65 = -5 + (n-1)5
65 = -5 + 5n - 5
70 = 5n
n = 14
Now, we can find the sum of the series using the formula:
Sn = n/2 * (a1 + an)
Sn = 14/2 * (-5 + 65)
Sn = 7 * 60
Sn = 420
So, the sum of the finite arithmetic series is 420.
Therefore, the answer is not in the options provided.
What is the sum of the finite arithmetic series?
(–5) + 0 + 5 + 10 + ... + 65
1. 900
2. 455
3. 450
4. 445
1 answer