Simple Interest
MCQs Math


Question:     Calculate the amount due if Jennifer borrowed a sum of $3250 at 8% simple interest for 4 years.


Correct Answer  $4290

Solution And Explanation

Solution

Given,

Principal (P) = $3250

Rate of Simple Interest (SI) = 8%

Time (t) = 4 years

Thus, Amount (A) = ?

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

Thus, here 8% simple interest means, Rate of Simple Interest (SI) is 8% 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) = $3250 × 8% × 4

= $3250 ×8/100 × 4

= 3250 × 8 × 4/100

= 26000 × 4/100

= 104000/100

= $1040

Thus, Simple Interest = $1040

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 = $3250 + $1040

= $4290

Thus, Amount to be paid = $4290 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 = $3250

Rate of Simple Interest (SI) or (R) = 8%

And, Time (t) = 4 years

Thus, Amount (A)

= $3250 + ($3250 × 8% × 4)

= $3250 + ($3250 ×8/100 × 4)

= $3250 + (3250 × 8 × 4/100)

= $3250 + (26000 × 4/100)

= $3250 + (104000/100)

= $3250 + $1040 = $4290

Thus, Amount (A) to be paid = $4290 Answer

Method (3) Unitary Method

Calculation of Amount using Unitary Method

Calculation of Interest using Unitary Method

Here, given Rate of Simple Interest = 8%

This, means, $8 per $100 per year

∵ For $100, the simple interest for 1 year = $8

∴ For $1, the simple interest for 1 year = 8/100

∴ For $3250, the simple interest in 1 year

= 8/100 × 3250

= 8 × 3250/100

= 26000/100 = $260

Thus, simple interest for 1 year = $260

Therefore, simple interest for 4 years

= Simple interest for 1 year × 4

= $260 × 4 = $1040

Thus, Simple Interest (SI) = $1040

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $3250 + $1040

= $4290

Thus, Amount to be paid = $4290 Answer


Similar Questions

(1) What amount does James have to pay after 6 years if he takes a loan of $3000 at 4% simple interest?

(2) Mary had to pay $3233 in order to furnish the loan taken 3 years before. If the rate of simple interest was 2% then find the sum borrowed.

(3) What amount will be due after 2 years if David borrowed a sum of $3200 at a 7% simple interest?

(4) Find the amount to be paid if Barbara borrowed a sum of $5550 at 5% simple interest for 8 years.

(5) Mark took a loan of $6800 at the rate of 10% simple interest per annum. If he paid an amount of $11560 to clear the loan, then find the time period of the loan.

(6) Charles took a loan of $5800 at the rate of 9% simple interest per annum. If he paid an amount of $11020 to clear the loan, then find the time period of the loan.

(7) Find the amount to be paid if Joseph borrowed a sum of $5700 at 3% simple interest for 8 years.

(8) Calculate the amount due if Mary borrowed a sum of $3050 at 5% simple interest for 4 years.

(9) Calculate the amount due if Susan borrowed a sum of $3650 at 6% simple interest for 3 years.

(10) Calculate the amount due if David borrowed a sum of $3400 at 9% simple interest for 3 years.


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