Simple Interest
Simple Interest - Important Points
| 1. | At what rate percent of simple interest per annum will a sum of money double in 8 years. |
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A. 12.5%
B. 13.5%
C. 11.5%
D. 14.5%
View Answer Discuss Work SpaceAnswer: option a
Explanation:
Let principal = P, Then, SI = P after 8 years
We know that SI = PTR/100 = P
Rate = [(100 x P)/ (P x 8)]% = 12.5% per annum
| 2. | How much time will take for an amount of Rs. 450 to yield Rs. 81 as interest at 4.5% per annum of simple interest ? |
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A. 4 years
B. 2.5 years
C. 3.5 years
D. 2 years
View Answer Discuss Work SpaceAnswer: option a
Explanation:
SI = PTR/100
Time = (100 x 81) / (450 x 4.5) = 4 years
| 3. | A sum was put at simple interest at a certain rate for 3 years. Had it been put at 2% higher rate, it would have fetched Rs 360 more. Find the sum. |
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A. Rs.4000
B. Rs.9000
C. Rs.5000
D. Rs.6000
View Answer Discuss Work SpaceAnswer: option d
Explanation:
Let sum = P and original rate of interest = R
Then, [(P * (R+2) * 3)/100] - [ (P * R * 3)/100] = 360
=> 3P*(R+2) - 3PR = 36000
=> 3PR + 6P - 3PR = 36000
=> 6P = 36000
=> P = 6000
| 4. | A certain sum earns simple interest of Rs. 1750 in 7 years. Had the interest been 2% more, how much more interest would it have earned? |
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A. Rs.35
B. Rs.245
C. Rs.350
D. cannot be determined
View Answer Discuss Work SpaceAnswer: option d
Explanation:
We need to know the S.I, principal and time to find the rate. Since the principal is not given, so data is inadequate.
| 5. | The difference between the simple interest received from two different sources on Rs. 3000 for 3 years is Rs. 27. The difference between their rates of interest is: |
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A. 0.1%
B. 0.2%
C. 0.3%
D. 0.4%
View Answer Discuss Work SpaceAnswer: option c
Explanation:
=> [3000 x (R1-R2) x 3]/100 = 27
=> 9000 x (R1-R2) = 2700
=> (R1-R2)= 2700/9000 = 0.3 %