Simple Interest
MCQs Math


Question:     Jennifer took a loan of $4500 at the rate of 8% simple interest per annum. If he paid an amount of $7380 to clear the loan, then find the time period of the loan.


Correct Answer  8

Solution And Explanation

Solution

Given,

Principal (P) = $4500

Rate of Simple Interest (R) = 8% per annum

Amount (A) = $7380

Thus, time (T) = ?

Method (1) Using Formula

Calculation of Simple Interest, when Principal and Amount are given

Formual 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 = $7380 – $4500 = $2880

Thus, Simple Interest = $2880

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 × 2880/4500 × 8

= 288000/36000

= 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) = $4500

Rate of Simple Interest (R) = 8% per annum

Simple Interest = $2880 (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 $4500

= 8/100 × 4500

= 8 × 4500/100

= 36000/100 = 360

Thus, simple Interest for 1 year = $360

Now,

∵ If the simple Interest is $360, then the time = 1 year

∴ If the simple Interest is $1, then the time = 1/360 years

∴ If the simple Interest is $2880, then the time = 1/360 × 2880 years

= 1 × 2880/360 years

= 2880/360 = 8 years

Thus, time (T) = 8 years Answer


Similar Questions

(1) If Karen paid $4266 to settle his loan which he had taken 4 years before at a simple interest of 2%, then find the loan taken.

(2) Calculate the amount due if Thomas borrowed a sum of $3800 at 10% simple interest for 3 years.

(3) How much loan did Ashley borrow 5 years ago at a rate of simple interest 5% per annum, if he paid $8187.5 to clear it?

(4) What amount will be due after 2 years if Mark borrowed a sum of $3700 at a 8% simple interest?

(5) Calculate the amount due if John borrowed a sum of $3200 at 9% simple interest for 3 years.

(6) Matthew had to pay $4830 in order to furnish the loan taken 3 years before. If the rate of simple interest was 5% then find the sum borrowed.

(7) In how much time a principal of $3000 will amount to $3450 at a simple interest of 5% per annum?

(8) What amount will be due after 2 years if Thomas borrowed a sum of $3400 at a 7% simple interest?

(9) Calculate the amount due if Christopher borrowed a sum of $4000 at 3% simple interest for 3 years.

(10) Calculate the amount due after 9 years if Mary borrowed a sum of $5050 at a rate of 2% simple interest.


NCERT Solution and CBSE Notes for class twelve, eleventh, tenth, ninth, seventh, sixth, fifth, fourth and General Math for competitive Exams. ©