Find the sum of first 24 terms of ap a1,A2,A3,........if it is known that a1+A5+A10+a15+a20+a24=225?

Asked by rraj.15266 | 25th Jul, 2017, 03:38: PM

Expert Answer:

begin mathsize 16px style straight a subscript 1 plus straight a subscript 5 plus straight a subscript 10 plus straight a subscript 15 plus straight a subscript 20 plus straight a subscript 24 equals 225
straight a plus straight a plus 4 straight d plus straight a plus 9 straight d plus straight a plus 14 straight d plus straight a plus 19 straight d plus straight a plus 23 straight d equals 225
6 straight a plus 69 straight d equals 225
2 straight a plus 23 straight d equals 75
straight a plus left parenthesis straight a plus 23 straight d right parenthesis equals 75
straight a plus straight l equals 75
24 to the power of th space end exponent term space equals 24 over 2 cross times open parentheses straight a plus straight l close parentheses equals 24 over 2 cross times 75 equals 900 end style

Answered by Sneha shidid | 25th Jul, 2017, 05:12: PM