Question

How many terms must be added in the A.P4,9,14,19.......To obtain 837?

Answer 1

Answer:

$suppose \: \: added \: \: terms \: = \: n \\ \\ 834 = \frac{n}{2} (2 \times 4 + (n - 1)5) \\ \\ 1668 = 8n + 5 {n}^{2} - 5n \\ \\solve \: \: this \: \: and \: \: get \: \: the \: \: terms.$