Question

(b) An arithmetic progression is such that the eighth term is three times the third term. Show that the sum of the first eight terms is four times the sum of the first four terms. [4]​

Answer 1

Answer:

3x = 18+3 and 3x × 4 times

3x × 4 = 12 and 18+3 = 21

hence 12 and 21 is divided by 3

hence 4 and 7