Question

A certain sum at simple interest becomes 1200 rs in 2 years and 1300 rs in 3 years find the principal and interest percent per annum

Answer 1

Answer:

Rs 4000

Step-by-step explanation:

Let the the principal was ₹ x. and rate of interest = r% p.a. , accordingly:-

(x.r.2)/100 = 1200. Or, x.r = 60000. ……………..(1)

x. [(1+r/100)^2 -1] = 1290.

or, x.(r/100).(2 +r/100) = 1290. , putting r= 60000/x from eqn. (1)

or, x.(600/x)(2 + 600//x)= 1290.

or, 600.(2 + 600/x) =1290.

or, 2 + 600/x = 1290/600 = 2 + 3/20.

or, 600/x = 3/20. => x = 600×20/3 = ₹ 4000. Answer.