Question

Rajesh deposited a sum of rupees 35000 in a bank for 5 years. He also invested rupees 50000 for the same period but at a rate 4% higher than the first. He got a total interest of rupees 34650 from both his deposits, after the end of 5 years. Find the rate of simple interest.

Answer 1

Answer:

5.8

Explanation:

let the rate for bank deposite is y

S.I. (1st)=(35000x5xy)/100=1750y

S.I.(2nd)=[50000x5x(y+4)]/100=2500y+10000

S.I.(1st)+S.I.(2nd)=34650

1750y+2500y+10000=34650

4250y=24650

y=24650/4250

y=5.8%

Answer 2

Rajesh deposited a sum of rupees 35000 in a bank for 5 years. He also invested rupees 50000 for the same period but at a rate 4% higher than the first. He got a total interest of rupees 34650 from both his deposits, after the end of 5 years. The rate of simple interest is 5.8% p.a.

Let the rate of simple interest be r% p.a.

For the first case,

Given, Principal amount (P) = Rs 35000

Time (T) = 5 years

We know, Simple Interest (S.I.) is given as :

S.I. = (P × R × T) ÷ 100

So, for the first case, SI is given as:

SI₁ = (35000 × r × 5) ÷ 100

SI₁ = 1750r

For the second case,

Given, Principal amount (P) = Rs 50000

Time (T) = 5 years

Rate is 4% more than the previous.

So, r = (r+4)% p.a

So, for the second case, SI is given as:

SI₂ = (50000 × [r+4] × 5) ÷ 100

SI₂ = 2500(r+4)

It is given that the sum of the total interests equal to Rs 34650

∴ SI₁ + SI₂ = 34650

⇒ 1750r + 2500(r+4) = 34650

⇒ 1750r + 2500r + 10000 = 34650

⇒ 4250r = 24650

⇒ r = 24650/4250 = 5.8

So, the rate% is equal to 5.8% p.a.