The simple interest on a sum of money is
45
9
of the sum. If the number of years is numerically 5 times of rate per cent per annum, then find the rate per cent per annum.
- A7%
- B2%
- C5%
- D3%
Solution & Step-by-step Explanation
Let the principal sum be P.
The Simple Interest (SI) is given as:
SI=
45
9
P=
5
1
P
Let the rate per cent per annum be R.
The number of years T is numerically 5 times the rate per cent:
T=5R
The standard formula for Simple Interest is:
SI=
100
P×R×T
Substitute the values into the formula:
5
1
P=
100
P×R×5R
5
1
=
100
5R
2
5
1
=
20
R
2
R
2
=
5
20
=4
R=
4
=2%
The Simple Interest (SI) is given as:
SI=
45
9
P=
5
1
P
Let the rate per cent per annum be R.
The number of years T is numerically 5 times the rate per cent:
T=5R
The standard formula for Simple Interest is:
SI=
100
P×R×T
Substitute the values into the formula:
5
1
P=
100
P×R×5R
5
1
=
100
5R
2
5
1
=
20
R
2
R
2
=
5
20
=4
R=
4
=2%