Question

Find the sum of first 50 terms in the sequence 10n-15.

Answer 1

12,000.

Explanation:

First term = 10(1) - 15 = -5

50th term = 10(50) - 15 = 485

Sum of 50 terms = (50/2)(-5 + 485)

= 25 * 480

= 12,000

Answer 2

485 bro just do it with calculator

Explanation:

10×n-15

10×50-15

485