Simple Interest
MCQs Math


Question:     Find the amount to be paid if Susan borrowed a sum of $5650 at 6% simple interest for 8 years.


Correct Answer  $8362

Solution And Explanation

Solution

Given,

Principal (P) = $5650

Rate of Simple Interest (SI) = 6%

Time (t) = 8 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) = $5650 × 6% × 8

= $5650 ×6/100 × 8

= 5650 × 6 × 8/100

= 33900 × 8/100

= 271200/100

= $2712

Thus, Simple Interest = $2712

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 = $5650 + $2712

= $8362

Thus, Amount to be paid = $8362 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 = $5650

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

And, Time (t) = 8 years

Thus, Amount (A)

= $5650 + ($5650 × 6% × 8)

= $5650 + ($5650 ×6/100 × 8)

= $5650 + (5650 × 6 × 8/100)

= $5650 + (33900 × 8/100)

= $5650 + (271200/100)

= $5650 + $2712 = $8362

Thus, Amount (A) to be paid = $8362 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 $5650, the simple interest in 1 year

= 6/100 × 5650

= 6 × 5650/100

= 33900/100 = $339

Thus, simple interest for 1 year = $339

Therefore, simple interest for 8 years

= Simple interest for 1 year × 8

= $339 × 8 = $2712

Thus, Simple Interest (SI) = $2712

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $5650 + $2712

= $8362

Thus, Amount to be paid = $8362 Answer


Similar Questions

(1) In how much time a principal of $3000 will amount to $3450 at a simple interest of 5% per annum?

(2) Calculate the amount due if Richard borrowed a sum of $3600 at 2% simple interest for 3 years.

(3) Jessica took a loan of $5500 at the rate of 6% simple interest per annum. If he paid an amount of $7480 to clear the loan, then find the time period of the loan.

(4) Calculate the amount due if Charles borrowed a sum of $3900 at 9% simple interest for 4 years.

(5) If Donna paid $5238 to settle his loan which he had taken 4 years before at a simple interest of 2%, then find the loan taken.

(6) Calculate the amount due if Mary borrowed a sum of $3050 at 5% simple interest for 3 years.

(7) Daniel took a loan of $6200 at the rate of 6% simple interest per annum. If he paid an amount of $8432 to clear the loan, then find the time period of the loan.

(8) Calculate the amount due after 10 years if Thomas borrowed a sum of $5800 at a rate of 4% simple interest.

(9) Find the amount to be paid if Jessica borrowed a sum of $5750 at 10% simple interest for 7 years.

(10) Christopher took a loan of $6000 at the rate of 6% simple interest per annum. If he paid an amount of $8880 to clear the loan, then find the time period of the loan.


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