Simple Interest
MCQs Math


Question:     What amount does Karen have to pay after 5 years if he takes a loan of $3950 at 5% simple interest?


Correct Answer  $4937.5

Solution And Explanation

Solution

Given,

Principal (P) = $3950

Rate of Simple Interest (SI) = 5%

Time (t) = 5 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) = $3950 × 5% × 5

= $3950 ×5/100 × 5

= 3950 × 5 × 5/100

= 19750 × 5/100

= 98750/100

= $987.5

Thus, Simple Interest = $987.5

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 = $3950 + $987.5

= $4937.5

Thus, Amount to be paid = $4937.5 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 = $3950

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

And, Time (t) = 5 years

Thus, Amount (A)

= $3950 + ($3950 × 5% × 5)

= $3950 + ($3950 ×5/100 × 5)

= $3950 + (3950 × 5 × 5/100)

= $3950 + (19750 × 5/100)

= $3950 + (98750/100)

= $3950 + $987.5 = $4937.5

Thus, Amount (A) to be paid = $4937.5 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 $3950, the simple interest in 1 year

= 5/100 × 3950

= 5 × 3950/100

= 19750/100 = $197.5

Thus, simple interest for 1 year = $197.5

Therefore, simple interest for 5 years

= Simple interest for 1 year × 5

= $197.5 × 5 = $987.5

Thus, Simple Interest (SI) = $987.5

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $3950 + $987.5

= $4937.5

Thus, Amount to be paid = $4937.5 Answer


Similar Questions

(1) Elizabeth had to pay $3864 in order to furnish the loan taken 3 years before. If the rate of simple interest was 4% then find the sum borrowed.

(2) Calculate the amount due if Richard borrowed a sum of $3600 at 2% simple interest for 4 years.

(3) Calculate the amount due after 9 years if Elizabeth borrowed a sum of $5450 at a rate of 8% simple interest.

(4) Find the amount to be paid if John borrowed a sum of $5200 at 4% simple interest for 7 years.

(5) Calculate the amount due after 9 years if William borrowed a sum of $5500 at a rate of 6% simple interest.

(6) Anthony took a loan of $6600 at the rate of 7% simple interest per annum. If he paid an amount of $10758 to clear the loan, then find the time period of the loan.

(7) What amount will be due after 2 years if Steven borrowed a sum of $3800 at a 8% simple interest?

(8) Calculate the amount due after 10 years if David borrowed a sum of $5400 at a rate of 6% simple interest.

(9) What amount does Charles have to pay after 5 years if he takes a loan of $3900 at 7% simple interest?

(10) Find the amount to be paid if David borrowed a sum of $5400 at 5% simple interest for 7 years.


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