Question

Find Sn for the arithmetic series where a1 = 3, an = 42, n = 14

Answer 1

To find Sn for an arithmetic series, you can use the following formula: Sn = (n/2) * (a1 + an).

In this case, Sn = (14/2)*(3 + 42) = 189.

To explain step-by-step:

1. Find the number of terms in the series, n = 14

2. Find the first term in the series, a1 = 3

3. Find the last term in the series, an = 42

4. Plug the values into the formula, Sn = (n/2)*(a1 + an)

5. Simplify the equation and solve, Sn = (14/2)*(3 + 42) = 189