Question

A collection of dimes is arranged in a triangular array with 17 coins in the base row, 16 in the next, 15 in the next, and so forth.

Answer 1

153 dimes

Explanation:

17 + 16 + 15 + 14 + 13 + 12 + 11 + 10 + 9 + 8 + 7 + 6 + 5 + 4 + 3 + 2 + 1 = 153

Answer 2

Good evening ,

Answer:

153 dimes.

Explanation:

1+2+3+...+17 = (17×18)/2 = (17×18)÷2 = 153 dimes.

it’s the sum of 17 terms of a geometric series.

:)