Question

If the last term of an ap is 136 and the tenth term from the end is 109 , then find the common difference of the ap

Answer 1

Answer:

The number of terms are 8.    

Step-by-step explanation:

Given : The sum n terms of an A.P is 136 the common difference is 4 and last term is 31.

To find : The number of terms?

Solution :

Common difference d=4

last term l=31

Sum of n terms is

The last term formula is

....(1)

The Sum of n terms formula is

Substitute the value of equation from (1),

Solving by quadratic formula,

The value of n can't be in fraction or decimal.

Therefore, The number of terms are 8.