Chapter 0.4, Problem 4E

To determine

To calculate:Have to find the 20^th term.

Answer to Problem 4E

The 20^th term is 205.

Explanation of Solution

Given information: 3, 8, 13, 18.......

Since: 3, 8, 13, 18.............n, it is a asthmatic progressive series, because the common difference are same.

Now, first term (a) $=3$ common difference (d ) $=8-3=5$

The n^th term of the Asthmatic progressive is $a_n=a+\left(n-1\right)d$

Have to find the 20^th term = $n_{20}=a+\left(20-1\right)d$

Calculation:

  $\begin{array}{l}\Rightarrow n_{20}=3+19\times 5\\ \Rightarrow n_{20}=3+95\\ \Rightarrow n_{20}=98\end{array}$