Question

Find the sum of four terms is 50 and the greater is 4times of least

Answer 1

S4=50 n=4 let first term=a and according to question last term is 4 times of the first than last term=4a as we know that Sn=n/2[a+an] therefore 50 = 4/2 [a+4a] = 25=5a now a=5 therefore 1st term =5 now last term=4×5=20