Question : ( 1 of 10 ) Margaret took a loan of $6700 at the rate of 7% simple interest per annum. If he paid an amount of $10452 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 8
Solution & Explanation
Solution
Given,
Principal (P) = $6700
Rate of Simple Interest (R) = 7% per annum
Amount (A) = $10452
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 = $10452 – $6700 = $3752
Thus, Simple Interest = $3752
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 × 3752/6700 × 7
= 375200/46900
= 8 years (using formula)
Thus, Time (T) = 8 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) = $6700
Rate of Simple Interest (R) = 7% per annum
Simple Interest = $3752 (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 = 7% of Principal
= 7% of $6700
= 7/100 × 6700
= 7 × 6700/100
= 46900/100 = 469
Thus, simple Interest for 1 year = $469
Now,
∵ If the simple Interest is $469, then the time = 1 year
∴ If the simple Interest is $1, then the time = 1/469 years
∴ If the simple Interest is $3752, then the time = 1/469 × 3752 years
= 1 × 3752/469 years
= 3752/469 = 8 years
Thus, time (T) = 8 years Answer
Similar Questions
(3) What amount will be due after 2 years if Joshua borrowed a sum of $3950 at a 4% simple interest?
(5) What amount does Joseph have to pay after 6 years if he takes a loan of $3700 at 2% simple interest?
(9) In how much time a principal of $3200 will amount to $3328 at a simple interest of 2% per annum?