The first and the last terms of an ap are 17 and 350 respectively If its common difference is 9,then find the sum of 38 terms
Share
The first and the last terms of an ap are 17 and 350 respectively If its common difference is 9,then find the sum of 38 terms
Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Verified answer
Answer:
hope it helps u ...
plz mark as brainliest ...
Given :
To Find :
Solution :
Let, l be the nth term of AP.
[tex]\sf : \implies a_{n} = l = 350[/tex]
Now, let's find sum of total number of terms in AP.
We know that :
[tex]\Large \underline{\boxed{\bf{ S_{n} = \dfrac{n}{2} ( a + a_{n} ) }}}[/tex]
We have :
[tex]\sf : \implies S_{38} = \dfrac{\cancel{38}^{19}}{\cancel{2}} ( 17 + 350 )[/tex]
[tex]\sf : \implies S_{38} = 19 (367)[/tex]
[tex]\sf : \implies S_{38} = 19 \times 367[/tex]
[tex]\sf : \implies S_{38} = 6973[/tex]
[tex]\large \underline{\boxed{\sf S_{38} = 6973}}[/tex]
Hence, There are 38 number of terms in given AP and their sum is 6973.