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4) In what time will a sum of money double itself at 10 % per annum? 5) Rohit deposited some money in a saving account. He got ₹ 12000 as simple interest after 5 years. If the interest is calculated at the rate of 6 % per annum, what was the amount that he deposited?
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4) In what time will a sum of money double itself at 10 % per annum? 5...
**4) In what time will a sum of money double itself at 10% per annum?**
To find the time it takes for a sum of money to double itself at a given interest rate, we can use the compound interest formula:
A = P(1 + r/n)^(nt)
Where:
A = final amount
P = principal amount (initial sum of money)
r = annual interest rate (as a decimal)
n = number of times interest is compounded per year
t = number of years
In this case, we want to find the time it takes for the principal amount to double, so the final amount is 2 times the principal amount:
2P = P(1 + 0.10/n)^(nt)
We can simplify this equation by dividing both sides by P:
2 = (1 + 0.10/n)^(nt)
To solve for t, we can take the logarithm of both sides:
log(2) = log((1 + 0.10/n)^(nt))
Using the logarithm properties, we can bring down the exponent:
log(2) = nt*log(1 + 0.10/n)
Dividing both sides by n*log(1 + 0.10/n):
t = log(2)/(n*log(1 + 0.10/n))
Since the question does not specify the compounding frequency, we can assume it is compounded annually (n = 1). Substituting this value into the equation:
t = log(2)/(1*log(1 + 0.10/1))
Simplifying further:
t = log(2)/log(1.10)
Using a calculator, we can find the approximate value of log(2)/log(1.10) to be 7.27 years.
Therefore, it will take approximately 7.27 years for the sum of money to double itself at an annual interest rate of 10%.
**5) Rohit deposited some money in a saving account. He got ₹12000 as simple interest after 5 years. If the interest is calculated at the rate of 6% per annum, what was the amount that he deposited?**
To find the amount Rohit deposited, we can use the simple interest formula:
Simple Interest = (Principal * Rate * Time) / 100
Given that the simple interest is ₹12000 and the rate is 6% per annum, we can substitute these values into the formula:
12000 = (Principal * 6 * 5) / 100
Simplifying the equation:
12000 = (Principal * 30) / 100
Multiplying both sides by 100:
1200000 = 30 * Principal
Dividing both sides by 30:
Principal = 1200000 / 30
Principal = ₹40000
Therefore, Rohit deposited ₹40000 in the savings account.
To find the time it takes for a sum of money to double itself at a given interest rate, we can use the compound interest formula:
A = P(1 + r/n)^(nt)
Where:
A = final amount
P = principal amount (initial sum of money)
r = annual interest rate (as a decimal)
n = number of times interest is compounded per year
t = number of years
In this case, we want to find the time it takes for the principal amount to double, so the final amount is 2 times the principal amount:
2P = P(1 + 0.10/n)^(nt)
We can simplify this equation by dividing both sides by P:
2 = (1 + 0.10/n)^(nt)
To solve for t, we can take the logarithm of both sides:
log(2) = log((1 + 0.10/n)^(nt))
Using the logarithm properties, we can bring down the exponent:
log(2) = nt*log(1 + 0.10/n)
Dividing both sides by n*log(1 + 0.10/n):
t = log(2)/(n*log(1 + 0.10/n))
Since the question does not specify the compounding frequency, we can assume it is compounded annually (n = 1). Substituting this value into the equation:
t = log(2)/(1*log(1 + 0.10/1))
Simplifying further:
t = log(2)/log(1.10)
Using a calculator, we can find the approximate value of log(2)/log(1.10) to be 7.27 years.
Therefore, it will take approximately 7.27 years for the sum of money to double itself at an annual interest rate of 10%.
**5) Rohit deposited some money in a saving account. He got ₹12000 as simple interest after 5 years. If the interest is calculated at the rate of 6% per annum, what was the amount that he deposited?**
To find the amount Rohit deposited, we can use the simple interest formula:
Simple Interest = (Principal * Rate * Time) / 100
Given that the simple interest is ₹12000 and the rate is 6% per annum, we can substitute these values into the formula:
12000 = (Principal * 6 * 5) / 100
Simplifying the equation:
12000 = (Principal * 30) / 100
Multiplying both sides by 100:
1200000 = 30 * Principal
Dividing both sides by 30:
Principal = 1200000 / 30
Principal = ₹40000
Therefore, Rohit deposited ₹40000 in the savings account.
Community Answer
4) In what time will a sum of money double itself at 10 % per annum? 5...
Answer
PXRxN/100=SI
Px5x6/100=12000
P=1200000/30
P=40000 rs
PXRxN/100=SI
Px5x6/100=12000
P=1200000/30
P=40000 rs
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4) In what time will a sum of money double itself at 10 % per annum? 5) Rohit deposited some money in a saving account. He got ₹ 12000 as simple interest after 5 years. If the interest is calculated at the rate of 6 % per annum, what was the amount that he deposited?
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4) In what time will a sum of money double itself at 10 % per annum? 5) Rohit deposited some money in a saving account. He got ₹ 12000 as simple interest after 5 years. If the interest is calculated at the rate of 6 % per annum, what was the amount that he deposited? for Class 7 2024 is part of Class 7 preparation. The Question and answers have been prepared according to the Class 7 exam syllabus. Information about 4) In what time will a sum of money double itself at 10 % per annum? 5) Rohit deposited some money in a saving account. He got ₹ 12000 as simple interest after 5 years. If the interest is calculated at the rate of 6 % per annum, what was the amount that he deposited? covers all topics & solutions for Class 7 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for 4) In what time will a sum of money double itself at 10 % per annum? 5) Rohit deposited some money in a saving account. He got ₹ 12000 as simple interest after 5 years. If the interest is calculated at the rate of 6 % per annum, what was the amount that he deposited?.
4) In what time will a sum of money double itself at 10 % per annum? 5) Rohit deposited some money in a saving account. He got ₹ 12000 as simple interest after 5 years. If the interest is calculated at the rate of 6 % per annum, what was the amount that he deposited? for Class 7 2024 is part of Class 7 preparation. The Question and answers have been prepared according to the Class 7 exam syllabus. Information about 4) In what time will a sum of money double itself at 10 % per annum? 5) Rohit deposited some money in a saving account. He got ₹ 12000 as simple interest after 5 years. If the interest is calculated at the rate of 6 % per annum, what was the amount that he deposited? covers all topics & solutions for Class 7 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for 4) In what time will a sum of money double itself at 10 % per annum? 5) Rohit deposited some money in a saving account. He got ₹ 12000 as simple interest after 5 years. If the interest is calculated at the rate of 6 % per annum, what was the amount that he deposited?.
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