Question

The first term of an A. P serie is2 and the common difference is 1/2.Find the 20th term.

Answer 1

here this is your answer..

Answer 2

Step-by-step explanation:

Given : The first term of an AP series is $2$ and common difference is $\frac12$ .

To find : The $20th$ term of AP.

Formula used : $nth$ term of an AP is

$an=a+(n-1)d$

a is the first term and d is the common difference of an AP.

• Calculation for $20th$ term

We have the first term(a) and common difference(d) of an AP and we have to find the value of $20th$ term, for a and d is given to us and n,

⇒  $n=20$

⇒  $a=2$

⇒  $d=\frac12$

by using formula,

⇒  $an=a+(n-1)d$

⇒  $a20=2+(20-1)*\frac12$

           $=2+\frac{19}2$

taking L.C.M as 2,

            $=\frac{4+19}{2}$

            $=\frac{23}{2}$

Hence we get the  $20th$ term of AP is $\frac{23}{2}$ .