Simple Interest
MCQs Math


Question:     Calculate the amount due after 9 years if Jennifer borrowed a sum of $5250 at a rate of 6% simple interest.


Correct Answer  $8085

Solution And Explanation

Solution

Given,

Principal (P) = $5250

Rate of Simple Interest (SI) = 6%

Time (t) = 9 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) = $5250 × 6% × 9

= $5250 ×6/100 × 9

= 5250 × 6 × 9/100

= 31500 × 9/100

= 283500/100

= $2835

Thus, Simple Interest = $2835

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 = $5250 + $2835

= $8085

Thus, Amount to be paid = $8085 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 = $5250

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

And, Time (t) = 9 years

Thus, Amount (A)

= $5250 + ($5250 × 6% × 9)

= $5250 + ($5250 ×6/100 × 9)

= $5250 + (5250 × 6 × 9/100)

= $5250 + (31500 × 9/100)

= $5250 + (283500/100)

= $5250 + $2835 = $8085

Thus, Amount (A) to be paid = $8085 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 $5250, the simple interest in 1 year

= 6/100 × 5250

= 6 × 5250/100

= 31500/100 = $315

Thus, simple interest for 1 year = $315

Therefore, simple interest for 9 years

= Simple interest for 1 year × 9

= $315 × 9 = $2835

Thus, Simple Interest (SI) = $2835

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $5250 + $2835

= $8085

Thus, Amount to be paid = $8085 Answer


Similar Questions

(1) Patricia had to pay $3528 in order to furnish the loan taken 3 years before. If the rate of simple interest was 4% then find the sum borrowed.

(2) How much loan did Laura borrow 5 years ago at a rate of simple interest 3% per annum, if he paid $9027.5 to clear it?

(3) Calculate the amount due after 9 years if David borrowed a sum of $5400 at a rate of 6% simple interest.

(4) Lisa took a loan of $6100 at the rate of 10% simple interest per annum. If he paid an amount of $10980 to clear the loan, then find the time period of the loan.

(5) Daniel had to pay $4346 in order to furnish the loan taken 3 years before. If the rate of simple interest was 2% then find the sum borrowed.

(6) Elizabeth had to pay $3657 in order to furnish the loan taken 3 years before. If the rate of simple interest was 2% then find the sum borrowed.

(7) In how much time a principal of $3000 will amount to $3270 at a simple interest of 3% per annum?

(8) Anthony took a loan of $6600 at the rate of 8% simple interest per annum. If he paid an amount of $10296 to clear the loan, then find the time period of the loan.

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

(10) How much loan did Kimberly borrow 5 years ago at a rate of simple interest 3% per annum, if he paid $7647.5 to clear it?


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