Question

The sum of an

a. P, whose first term is 4 and the last term is 146 is 7171. Determine the value of n

Answer 1

Answer:

Step-by-step explanation:

a=4

last term=146

Sum=7171

nth term of an AP = a+ (n-1)d

           146=4+(n-1)d

            142=(n-1)d

           

sum of n terms of an AP is= (n/2)(2a+(n-1)d)

            7171= (n/2)(8+(n-1)d)

            14342=n(8+(n-1)d)

14342=n(8+142)

14342=150n

n=14342/150=95.61

but n can't be in fraction

therefore n=96 terms