Simple Interest
MCQs Math


Question:     What amount will be due after 2 years if Christopher borrowed a sum of $3500 at a 5% simple interest?


Correct Answer  $3850

Solution And Explanation

Solution

Given,

Principal (P) = $3500

Rate of Simple Interest (SI) = 5%

Time (t) = 2 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) = $3500 × 5% × 2

= $3500 ×5/100 × 2

= 3500 × 5 × 2/100

= 17500 × 2/100

= 35000/100

= $350

Thus, Simple Interest = $350

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 = $3500 + $350

= $3850

Thus, Amount to be paid = $3850 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 = $3500

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

And, Time (t) = 2 years

Thus, Amount (A)

= $3500 + ($3500 × 5% × 2)

= $3500 + ($3500 ×5/100 × 2)

= $3500 + (3500 × 5 × 2/100)

= $3500 + (17500 × 2/100)

= $3500 + (35000/100)

= $3500 + $350 = $3850

Thus, Amount (A) to be paid = $3850 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 $3500, the simple interest in 1 year

= 5/100 × 3500

= 5 × 3500/100

= 17500/100 = $175

Thus, simple interest for 1 year = $175

Therefore, simple interest for 2 years

= Simple interest for 1 year × 2

= $175 × 2 = $350

Thus, Simple Interest (SI) = $350

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $3500 + $350

= $3850

Thus, Amount to be paid = $3850 Answer


Similar Questions

(1) Thomas had to pay $4370 in order to furnish the loan taken 3 years before. If the rate of simple interest was 5% then find the sum borrowed.

(2) Donald took a loan of $7000 at the rate of 6% simple interest per annum. If he paid an amount of $10780 to clear the loan, then find the time period of the loan.

(3) Find the amount to be paid if Jennifer borrowed a sum of $5250 at 10% simple interest for 8 years.

(4) Linda took a loan of $4700 at the rate of 7% simple interest per annum. If he paid an amount of $6674 to clear the loan, then find the time period of the loan.

(5) Joseph took a loan of $5400 at the rate of 7% simple interest per annum. If he paid an amount of $8046 to clear the loan, then find the time period of the loan.

(6) Find the amount to be paid if William borrowed a sum of $5500 at 2% simple interest for 8 years.

(7) Calculate the amount due if Richard borrowed a sum of $3600 at 7% simple interest for 4 years.

(8) 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.

(9) Mark took a loan of $6800 at the rate of 10% simple interest per annum. If he paid an amount of $10880 to clear the loan, then find the time period of the loan.

(10) William took a loan of $5000 at the rate of 8% simple interest per annum. If he paid an amount of $9000 to clear the loan, then find the time period of the loan.


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