Simple Interest
MCQs Math


Question:     Calculate the amount due after 9 years if John borrowed a sum of $5200 at a rate of 6% simple interest.


Correct Answer  $8008

Solution And Explanation

Solution

Given,

Principal (P) = $5200

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) = $5200 × 6% × 9

= $5200 ×6/100 × 9

= 5200 × 6 × 9/100

= 31200 × 9/100

= 280800/100

= $2808

Thus, Simple Interest = $2808

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 = $5200 + $2808

= $8008

Thus, Amount to be paid = $8008 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 = $5200

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

And, Time (t) = 9 years

Thus, Amount (A)

= $5200 + ($5200 × 6% × 9)

= $5200 + ($5200 ×6/100 × 9)

= $5200 + (5200 × 6 × 9/100)

= $5200 + (31200 × 9/100)

= $5200 + (280800/100)

= $5200 + $2808 = $8008

Thus, Amount (A) to be paid = $8008 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 $5200, the simple interest in 1 year

= 6/100 × 5200

= 6 × 5200/100

= 31200/100 = $312

Thus, simple interest for 1 year = $312

Therefore, simple interest for 9 years

= Simple interest for 1 year × 9

= $312 × 9 = $2808

Thus, Simple Interest (SI) = $2808

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $5200 + $2808

= $8008

Thus, Amount to be paid = $8008 Answer


Similar Questions

(1) Sandra took a loan of $6900 at the rate of 6% simple interest per annum. If he paid an amount of $10626 to clear the loan, then find the time period of the loan.

(2) What amount does James have to pay after 5 years if he takes a loan of $3000 at 10% simple interest?

(3) What amount does James have to pay after 6 years if he takes a loan of $3000 at 3% simple interest?

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

(5) Calculate the amount due if Susan borrowed a sum of $3650 at 4% simple interest for 4 years.

(6) How much loan did Stephanie borrow 5 years ago at a rate of simple interest 5% per annum, if he paid $9437.5 to clear it?

(7) How much loan did James borrow 5 years ago at a rate of simple interest 5% per annum, if he paid $6250 to clear it?

(8) James had to pay $3450 in order to furnish the loan taken 3 years before. If the rate of simple interest was 5% then find the sum borrowed.

(9) Find the amount to be paid if Patricia borrowed a sum of $5150 at 9% simple interest for 8 years.

(10) Lisa took a loan of $6100 at the rate of 10% simple interest per annum. If he paid an amount of $9760 to clear the loan, then find the time period of the loan.


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