Simple interest
- What equal instalment of annual payment will discharge a debt which is due as 848 at the end of 4 years at 4% per annum simple interest ?
-
View Hint View Answer Discuss in Forum
Let each instalment be p. Then,
According to question ,
p + p × 4 × 1 
+ p + p × 4 × 2 + p + p × 4 × 3 + p = 848 100 100 100 ⇒ x + p + p + 2p + p + 3p + p = 848 25 25 25 ⇒ 26p + 27p + 28p + p = 848 25 25 25 ⇒ 26p + 27p + 28p + 25p = 848 25
⇒ 106p = 848 × 25⇒ p = 848 × 25 = ₹ 200 106
Second method to solve this question :
Here, A = ₹ 848, T = 4 years, r = 4%
Correct Option: B
Let each instalment be p. Then,
According to question ,p + p × 4 × 1 + p + p × 4 × 2 + p + p × 4 × 3 + p = 848 100 100 100 ⇒ x + p + p + 2p + p + 3p + p = 848 25 25 25 ⇒ 26p + 27p + 28p + p = 848 25 25 25 ⇒ 26p + 27p + 28p + 25p = 848 25
⇒ 106p = 848 × 25⇒ p = 848 × 25 = ₹ 200 106
Second method to solve this question :
Here, A = ₹ 848, T = 4 years, r = 4%Equal instalment = 848 × 200 4[200 + (4 - 1) 4] Equal instalment = 848 × 200 = ₹ 200 4 × 212
- A part of ₹ 1500 was lent at 10% per annum and the rest at 7% per annum simple interest. The total interest earned in three years was ₹ 396. The sum lent at 10% was
-
View Hint View Answer Discuss in Forum
Let p be lent at 10% per annum.
∴ (1500 – p ) is lent at 7% per annum.Now, p × 10 × 3 + (1500 - p) × 7 × 3 = 396 100 100
Correct Option: A
Let p be lent at 10% per annum.
∴ (1500 – p ) is lent at 7% per annum.Now, p × 10 × 3 + (1500 - p) × 7 × 3 = 396 100 100
⇒ 30p + 31500 – 21p = 39600
⇒ 9p = 39600 – 31500
⇒ p = 8100 ÷ 9 = ₹ 900
- Ramesh deposited 15600 in a fixed deposit at the rate of 10% per annum simple interest. After every second year, he adds his interest earnings to the principal. The interest at the end of fourth year is
-
View Hint View Answer Discuss in Forum
According to question ,
SI earned after two years = 15600 × 10 × 2 = ₹ 3120 100
∴ Principal for next two years = ₹ (15600 + 3120) = ₹ 18720
Correct Option: D
According to question ,
SI earned after two years = 15600 × 10 × 2 = ₹ 3120 100
∴ Principal for next two years = ₹ (15600 + 3120) = ₹ 18720SI earned at the end of fourth year = 18720 × 10 × 1 = ₹ 1872 100
- An old article is available for ₹ 12,000 at cash payment or is available for ₹ 7,000 cash payment and a monthly instalment of ₹630 for 8 months. The rate per cent per annum is
-
View Hint View Answer Discuss in Forum
As per the given in question , we have
Simple Interest = (7000 + 630 × 8) – 12000
Simple Interest = (7000 + 5040) – 12000
Simple Interest = 12040 – 12000 = 40
Total Principal = 5000 + 4370 + 3740 + 3110 + 2480 + 1850 + 1220 + 590 = ₹ 22360Correct Option: A
As per the given in question , we have
Simple Interest = (7000 + 630 × 8) – 12000
Simple Interest = (7000 + 5040) – 12000
Simple Interest = 12040 – 12000 = 40
Total Principal = 5000 + 4370 + 3740 + 3110 + 2480 + 1850 + 1220 + 590 = ₹ 22360
Rate = 40 × 100 ×12 ≈ 2.1% 22360 × 1
- A sum of ₹ 10,000 is lent partly at 8% and remaining at 10% per annum. If the yearly interest on the average is 9.2%, the two parts are :
-
View Hint View Answer Discuss in Forum
Let p be lent at 8%, then (10000 – p) is lent at 10%.
According to question ,∴ 10000 × 9.2 × t = p × 8 × t + (10000 - p) × 10 × t 100 100 100 ⇒ 920000 = 8pt + (10000 - p)10t 100 100 100
Correct Option: A
Let p be lent at 8%, then (10000 – p) is lent at 10%.
According to question ,∴ 10000 × 9.2 × t = p × 8 × t + (10000 - p) × 10 × t 100 100 100 ⇒ 920000 = 8pt + (10000 - p)10t 100 100 100
⇒ 92000t = 8pt + (10000 – p) 10t
⇒ 92000t = 8pt + (10000 – p) 10t
⇒ 92000 = 8p + 100000 – 10p
⇒ 2p = 8000
⇒ p = 4000
∴ First part = ₹ 4000
Second part = 10000 - 4000 = ₹ 6000
