Question

the first and the last terms of an ap are 17 and 350 respectively. if the common difference is 9, how many terms are there and what is their sum ?​

Answer 1

Answer:

n=38, S=6973

Step-by-step explanation:

Given:

a = 17

l = 350

d = 9

To find:

n, S

Solution:

Total no. of terms in AP can be given as n

nth term is l, which is the last term

[a]n = l

or l = a + (n-1)d

or 350 = 17 + (n-1)9

or 333 = (n-1)9

or ³³³/9 = n-1

or n-1 = 37

or n = 38

thus, the 38th term is the last term and there are 38 terms in the AP

Sum of all terms in the AP is

[S]n = n/2[a + l]

or [S]38 = ³⁸/2[17 + 350]

or [S]38 = 19[367]

or [S]38 = 6973

Hope it helps you :)

Pls current any mistakes in the comments...

Kindly mark me as the brainliest...

Answer 2

⬆️⬆️⬆️⬆️⬆️⬆️⬆️⬆️⬆️⬆️⬆️⬆️⬆️⬆️⬆️⬆️

REFER TO THE ATTACHMENT FOR ANSWER

HOPE IT HELPS YOU....✌️❣️✌️❣️✌️

THANK YOU.....