Answer:
38,710.
Step-by-step explanation:
This is an arithmetic series with common difference 8 , first term a = 7 and last term L = 783.
The number of terms n = (783 - 7) / 8 + 1 = 98
Sum of 98 terms = (n/2)[a + L)
= (98/2)(7 + 783)
= 49 * 790
= 38,710.
