Question : ( 1 of 10 ) Sarah took a loan of $5700 at the rate of 8% simple interest per annum. If he paid an amount of $8892 to clear the loan, then find the time period of the loan.
(A) 258.39 km(B) 172.26 km
(C) 215.33 km
(D) 137.81 km
Correct Answer 7
Solution & Explanation
Solution
Given,
Principal (P) = $5700
Rate of Simple Interest (R) = 8% per annum
Amount (A) = $8892
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 = $8892 – $5700 = $3192
Thus, Simple Interest = $3192
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 × 3192/5700 × 8
= 319200/45600
= 7 years (using formula)
Thus, Time (T) = 7 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) = $5700
Rate of Simple Interest (R) = 8% per annum
Simple Interest = $3192 (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 = 8% of Principal
= 8% of $5700
= 8/100 × 5700
= 8 × 5700/100
= 45600/100 = 456
Thus, simple Interest for 1 year = $456
Now,
∵ If the simple Interest is $456, then the time = 1 year
∴ If the simple Interest is $1, then the time = 1/456 years
∴ If the simple Interest is $3192, then the time = 1/456 × 3192 years
= 1 × 3192/456 years
= 3192/456 = 7 years
Thus, time (T) = 7 years Answer
Similar Questions
(2) Calculate the amount due if William borrowed a sum of $3500 at 6% simple interest for 4 years.
(4) What amount will be due after 2 years if James borrowed a sum of $3000 at a 7% simple interest?
(10) What amount will be due after 2 years if Kenneth borrowed a sum of $4000 at a 8% simple interest?