Question

An initial investment of $1,500 was made in the first month. In the second month, $1,507 was invested, while in the third month, the investment increased to $1,514. The monthly investments then continued using this arithmetic progression. How much was the portfolio worth after 60 months?

Answer 1

$102390

Explanation:

An initial investment of $1,500 was made in the first month. In the second month, $1,507 was invested, while in the third month, the investment increased to $1,514.

The monthly investments then continued using this arithmetic progression up to 60 months.

Therefore, total portfolio worth after 60 months will be

= 1500 + 1507 + 1514 + ........... + (1500 + 59 × 7)

= 1500 + 1507 + 1514 + ............. + 1913

This is an A.P. series whose sum will be

`S_(60) = (60)/(2)(1500 + 1913) = 102390` dollars. (Answer)