Question

which term of the AP-( - 7, - 12, - 17, - 22) will be - 82

Answer 1

Given:

The AP - ( - 7, - 12, - 17, - 22)

To find:

Which term of the AP will be - 82

Solution:

Using the formula of AP -

= a + (n - 1)d

Where the first value a = - 7

Common difference = d = - 12 - ( -7) = - 5

Substituting the values -  

= - 82 = - 7 + (n - 1)(- 5)

= - 82 + 7 = ( n-1) ( -5)

= - 75 = 5 - 5n

= - 75 - 5 = 5n

= - 80 = - 5n

= 16 = n or

n = 16

Answer: The 16th term of A.P. will be - 82.