In an ap d sum of d 1st ten terms is 50 nd d fifth term is 3times the 2nd term.find the first nd d sum of d 1st 20 terms

2 answers

Re-type in English please.
10a + 45d =50
.a +4d = 3a + 3d =a =d/2
10(d/2) + 45d = 50. .d=1 . a=1/2. . .
S20=20(1/2) +190(1) =200. . Ans =200