Question:
In how much time a principal of $3150 will amount to $3402 at a simple interest of 4% per annum?
Correct Answer
2
Solution And Explanation
Solution
Given,
Principal (P) = $3150
Rate of Simple Interest (R) = 4% per annum
Amount (A) = $3402
Thus, time (T) = ?
Method (1) Using Formula
Calculation of Simple Interest, when Principal and Amount are givenFormual to Calculate Simple Interest when Principal and Amount are given
We know that, Amount (A) = Principal (P) + Simple Interest (SI)
⇒ Simple Interest (SI) = Amount – Principal
⇒ SI = $3402 – $3150 = $252
Thus, Simple Interest = $252
Calculation of the Time using forumula when Amount, Simple Interest and Principal are known
Formula to find the Time (T)
Time (T) = 100 × Simple Interest/Principal × Rate of Interest
⇒ T = 100 × SI/P × R
Thus, Time (T) = 100 × 252/3150 × 4
= 25200/12600
= 2 years (using formula)
Thus, Time (T) = 2 years (from time taken before calculation)Answer
Calculation of the Time using Unitary Method when Amount, Simple Interest and Principal are known
Here, we have
Principal (P) = $3150
Rate of Simple Interest (R) = 4% per annum
Simple Interest = $252 (As calculated above by subtracting Principal from the Amount given)
We know that, interest is calculated on the basis of the Principal.
This means Simple Interest for 1 year = Rate of simple interest × Principal
Thus, Simple Interest for 1 year = 4% of Principal
= 4% of $3150
= 4/100 × 3150
= 4 × 3150/100
= 12600/100 = 126
Thus, simple Interest for 1 year = $126
Now,
∵ If the simple Interest is $126, then the time = 1 year
∴ If the simple Interest is $1, then the time = 1/126 years
∴ If the simple Interest is $252, then the time = 1/126 × 252 years
= 1 × 252/126 years
= 252/126 = 2 years
Thus, time (T) = 2 years Answer
Similar Questions
(1) What amount does Barbara have to pay after 6 years if he takes a loan of $3550 at 7% simple interest?
(2) If John borrowed $3200 from a bank at a rate of 2% simple interest per annum then find the amount to be paid after 2 years.
(3) Calculate the amount due after 10 years if Susan borrowed a sum of $5650 at a rate of 6% simple interest.
(4) What amount will be due after 2 years if Steven borrowed a sum of $3800 at a 6% simple interest?
(5) What amount will be due after 2 years if John borrowed a sum of $3100 at a 10% simple interest?
(6) Calculate the amount due if John borrowed a sum of $3200 at 10% simple interest for 4 years.
(7) Richard took a loan of $5200 at the rate of 6% simple interest per annum. If he paid an amount of $8320 to clear the loan, then find the time period of the loan.
(8) Anthony took a loan of $6600 at the rate of 6% simple interest per annum. If he paid an amount of $9768 to clear the loan, then find the time period of the loan.
(9) How much loan did Timothy borrow 5 years ago at a rate of simple interest 4% per annum, if he paid $8880 to clear it?
(10) If John paid $3840 to settle his loan which he had taken 4 years before at a simple interest of 5%, then find the loan taken.