Question

The simple interest on a certain sum for 3 years at 7% p.a. is 225 more than the simple interest on the same sum
for 4 years at 5% p.a. Find the sum.​

Answer 1

Answer:

let principal be x

n=4 years

r= 5% p.a

SI= x*4*5/100

SI= x/5

II deposit

Principal =x

r=7

n= 3 1/2 years = 7/2 years

Si= (x*7*7)/(2*100)

SI=49x/200

II deposit interest -I deposit interest =225

49x/200 -x/5 =225

LCD = 200

multiply by 200 to eliminate the denominator

49x-40x=225*200

9x=225*200

x=225*200/9

x= Rs 5,000 the principal