Simple Interest
MCQs Math


Question:     What amount does Joseph have to pay after 6 years if he takes a loan of $3700 at 5% simple interest?


Correct Answer  $4810

Solution And Explanation

Solution

Given,

Principal (P) = $3700

Rate of Simple Interest (SI) = 5%

Time (t) = 6 years

Thus, Amount (A) = ?

The Rate of Interest is always calculated per annum, i.e. per year.

Thus, here 5% simple interest means, Rate of Simple Interest (SI) is 5% per annum.

Method (1) Using Formula

Calculation of Simple Interest

Formula to Calculate Simple Interest

Simple Interest (SI) = Principal × Rate × Time

Thus, Simple Interest (SI) = $3700 × 5% × 6

= $3700 ×5/100 × 6

= 3700 × 5 × 6/100

= 18500 × 6/100

= 111000/100

= $1110

Thus, Simple Interest = $1110

Calculation of Amount

The total money paid to the lender by a borrower is called the Amount.

In other words, sum of priciple and interest is called the Amount.

Formula to Calculate the Amount

Amount = Principal + Interest

Thus, Amount = $3700 + $1110

= $4810

Thus, Amount to be paid = $4810 Answer

Method (2)

Calculation of Amount when Principal, Rate of Simple Interest and Time are given

Calculation of Amount directly using Principal, SI, and Time

Formula to calculate the Amount

Amount (A) = Principal (P) + Principal(P) × Rate of Interest (SI) × Time (t)

⇒ A = P + PRT

Here in the question, P = $3700

Rate of Simple Interest (SI) or (R) = 5%

And, Time (t) = 6 years

Thus, Amount (A)

= $3700 + ($3700 × 5% × 6)

= $3700 + ($3700 ×5/100 × 6)

= $3700 + (3700 × 5 × 6/100)

= $3700 + (18500 × 6/100)

= $3700 + (111000/100)

= $3700 + $1110 = $4810

Thus, Amount (A) to be paid = $4810 Answer

Method (3) Unitary Method

Calculation of Amount using Unitary Method

Calculation of Interest using Unitary Method

Here, given Rate of Simple Interest = 5%

This, means, $5 per $100 per year

∵ For $100, the simple interest for 1 year = $5

∴ For $1, the simple interest for 1 year = 5/100

∴ For $3700, the simple interest in 1 year

= 5/100 × 3700

= 5 × 3700/100

= 18500/100 = $185

Thus, simple interest for 1 year = $185

Therefore, simple interest for 6 years

= Simple interest for 1 year × 6

= $185 × 6 = $1110

Thus, Simple Interest (SI) = $1110

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $3700 + $1110

= $4810

Thus, Amount to be paid = $4810 Answer


Similar Questions

(1) In how much time a principal of $3200 will amount to $3840 at a simple interest of 4% per annum?

(2) How much loan did Susan borrow 5 years ago at a rate of simple interest 2% per annum, if he paid $6215 to clear it?

(3) Calculate the amount due if Michael borrowed a sum of $3300 at 9% simple interest for 4 years.

(4) Calculate the amount due after 9 years if Michael borrowed a sum of $5300 at a rate of 4% simple interest.

(5) Calculate the amount due if James borrowed a sum of $3000 at 4% simple interest for 3 years.

(6) Elizabeth took a loan of $4900 at the rate of 8% simple interest per annum. If he paid an amount of $8036 to clear the loan, then find the time period of the loan.

(7) Calculate the amount due after 9 years if Robert borrowed a sum of $5100 at a rate of 3% simple interest.

(8) Calculate the amount due after 9 years if John borrowed a sum of $5200 at a rate of 7% simple interest.

(9) Find the amount to be paid if Jessica borrowed a sum of $5750 at 5% simple interest for 7 years.

(10) If Patricia paid $3780 to settle his loan which he had taken 4 years before at a simple interest of 5%, then find the loan taken.


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