Question

The salary scale for a senior officer starts at N57000

per annum. A rise of N2800 is given at the end of each
Find the total amount of money that the officer will
year.
earn in 14 years.​

Answer 1

N1,052,800.

Explanation:

The starting salary of the officer = N57,000

Increase per annum =N2,800

The given pattern forms an arithmetic sequence since the annual salary increases by a fixed amount.

We are to determine the total amount of money that the officer will earn in 14 years.​

Sum of an arithmetic sequence,
`S_n=(n)/(2)[2a+(n-1)d]$ ,where: \left\{\begin{array}{lll}$First term, a=57,000\\$Common difference, d=2,800\\$Number of terms, n=14\end{array}\right`

`S_(14)=(14)/(2)[2(57,000)+(14-1)(2,800)]\\=7[114,000+13*2800]\\=7[150,400]\\=1,052,800`

At the end of 14 years, the total amount earned by the officer will be N1,052,800.