Question

Find the 20th term from the end of the AP 23, 18, 13,............-253.
Urgent plz.

Answer 1

Given:

The arithmetic progression is 23, 18, 13,....-253

To find:

The 20th term of the arithmetic progression.

Solution:

The first term of the arithmetic progression a1= 23

And the common difference of the arithmetic progression is 18-23 = -5

We know that nth term of an Arithmetic progression is given by:

an = a1 + (n-1) d

Putting the values to find the 20th term:

an = 23 + (20-1)(-5)

= 23 + (19)(-5)

= 23 - 95

= -72

Therefore the 20th term of the arithmetic progression is -72.