5 Deepak BoraNewbie Asked: August 11, 2020In: CBSE, ICSE If the 5th and 12th terms of an AP are -4 and -18 respectively, find the sum of first 20 terms of the AP. 5 Here the two terms of an AP is given you have to find the sum of first n term of ...Read more arithmetic progressionexercise 11 cicse&cbse boardquestion no. 18rs aggarwal