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:

No of Terms = 38

Total Sum = 6973

Step-by-step explanation:

First term = a = 17

Last term = l = 350

Common Difference = d = 9

To find the no. of terms

Use the Formula = an = a + ( n - 1 ) d

=> 350 = 17 + ( n - 1 ) 9

=> 350 = 17 + 9n − 9

=> 342 = 9n => n = 38

Now ,

Total Sum = Sn = n/2 { 2a + ( n - 1 ) d

=> S38 = 38/2 { 2×17 + (38 - 1) 9

=> S38 = 19 (34 + 333)

= 6973

Hence , there are 38 terms and their sum is equal to 6973.

Hope it helps you...

Answer 2

Answer:

Here is your answer ll

Hope it helps you