Arithemetic Mean (A.M)

Exercise:

A man is able to save N50.00 of his salary in a particular year.  After, every year he saved N20.00 more than the preceding year.  How long does it take him to save N4370?  JAMB

Assignment

1. The first and last terms of an A.P are 21 and -47 respectively. If the sum of the series is given as -234.  Calculate (a) the number of terms in the A.P  (b) the sum of the first 18 terms
2. Yusuf has just secured a job in a big company as a clerical officer. His starting salary is N180, 000 per annum with annual investment of N2, 000.  Determine his salary in the 20^th year and find his total salary he would have and in the first 20 yrs.