Simple Interest
MCQs Math


Question:     Calculate the amount due if Sarah borrowed a sum of $3850 at 6% simple interest for 3 years.


Correct Answer  $4543

Solution And Explanation

Solution

Given,

Principal (P) = $3850

Rate of Simple Interest (SI) = 6%

Time (t) = 3 years

Thus, Amount (A) = ?

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

Thus, here 6% simple interest means, Rate of Simple Interest (SI) is 6% 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) = $3850 × 6% × 3

= $3850 ×6/100 × 3

= 3850 × 6 × 3/100

= 23100 × 3/100

= 69300/100

= $693

Thus, Simple Interest = $693

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 = $3850 + $693

= $4543

Thus, Amount to be paid = $4543 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 = $3850

Rate of Simple Interest (SI) or (R) = 6%

And, Time (t) = 3 years

Thus, Amount (A)

= $3850 + ($3850 × 6% × 3)

= $3850 + ($3850 ×6/100 × 3)

= $3850 + (3850 × 6 × 3/100)

= $3850 + (23100 × 3/100)

= $3850 + (69300/100)

= $3850 + $693 = $4543

Thus, Amount (A) to be paid = $4543 Answer

Method (3) Unitary Method

Calculation of Amount using Unitary Method

Calculation of Interest using Unitary Method

Here, given Rate of Simple Interest = 6%

This, means, $6 per $100 per year

∵ For $100, the simple interest for 1 year = $6

∴ For $1, the simple interest for 1 year = 6/100

∴ For $3850, the simple interest in 1 year

= 6/100 × 3850

= 6 × 3850/100

= 23100/100 = $231

Thus, simple interest for 1 year = $231

Therefore, simple interest for 3 years

= Simple interest for 1 year × 3

= $231 × 3 = $693

Thus, Simple Interest (SI) = $693

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $3850 + $693

= $4543

Thus, Amount to be paid = $4543 Answer


Similar Questions

(1) Sarah took a loan of $5700 at the rate of 9% simple interest per annum. If he paid an amount of $10317 to clear the loan, then find the time period of the loan.

(2) Calculate the amount due after 9 years if Karen borrowed a sum of $5950 at a rate of 5% simple interest.

(3) Find the amount to be paid if John borrowed a sum of $5200 at 8% simple interest for 7 years.

(4) What amount will be due after 2 years if James borrowed a sum of $3000 at a 8% simple interest?

(5) Find the amount to be paid if John borrowed a sum of $5200 at 10% simple interest for 8 years.

(6) What amount does Michael have to pay after 5 years if he takes a loan of $3300 at 6% simple interest?

(7) What amount will be due after 2 years if Kenneth borrowed a sum of $4000 at a 5% simple interest?

(8) Christopher took a loan of $6000 at the rate of 9% simple interest per annum. If he paid an amount of $10320 to clear the loan, then find the time period of the loan.

(9) Find the amount to be paid if Richard borrowed a sum of $5600 at 4% simple interest for 8 years.

(10) Calculate the amount due after 9 years if Michael borrowed a sum of $5300 at a rate of 8% simple interest.


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