Question

Q. 4 The Sum Of The Third And The Ninth Term Of An AP Is 10. Find A Possible Sum Of The First 11 Terms Of This AP.​

Answer 1

Answer:

The third and ninth terms of an 11 term AP are a pair of corresponding terms of the AP. Hence, their average would be the average of the AP. This gives us the required sum of the AP as 11 × 5 = 55.