Question

Find the 20th term from the last term of the AP: 3.8.13..253.

Answer 1

Let,

a(first term)=3

t2(second term)=8

d(common difference)=second term - first term

=8-3

=5

20th term=a+(n-1)d

=3+(20-1)5

=3+19*5

=3+95

=98

Answer 2

Answer:

20th term from last term is 32th term=158

Step-by-step explanation:

Here a=3, a2=8

d=a2-a

d=5

let an=253

a+(n-1)d=253

putting values

3+(n-1)5=253

n=51

so,20th term from last is 51-19=32th term

so,we have to find a32

an=a+(n-1)d

a32=3+(32-1)5

a32=3+(31)5

a32=3+155

a32=158