Simple Interest
MCQs Math


Question:     What amount does Joseph have to pay after 5 years if he takes a loan of $3700 at 10% simple interest?


Correct Answer  $5550

Solution And Explanation

Solution

Given,

Principal (P) = $3700

Rate of Simple Interest (SI) = 10%

Time (t) = 5 years

Thus, Amount (A) = ?

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

Thus, here 10% simple interest means, Rate of Simple Interest (SI) is 10% 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) = $3700 × 10% × 5

= $3700 ×10/100 × 5

= 3700 × 10 × 5/100

= 37000 × 5/100

= 185000/100

= $1850

Thus, Simple Interest = $1850

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 = $3700 + $1850

= $5550

Thus, Amount to be paid = $5550 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 = $3700

Rate of Simple Interest (SI) or (R) = 10%

And, Time (t) = 5 years

Thus, Amount (A)

= $3700 + ($3700 × 10% × 5)

= $3700 + ($3700 ×10/100 × 5)

= $3700 + (3700 × 10 × 5/100)

= $3700 + (37000 × 5/100)

= $3700 + (185000/100)

= $3700 + $1850 = $5550

Thus, Amount (A) to be paid = $5550 Answer

Method (3) Unitary Method

Calculation of Amount using Unitary Method

Calculation of Interest using Unitary Method

Here, given Rate of Simple Interest = 10%

This, means, $10 per $100 per year

∵ For $100, the simple interest for 1 year = $10

∴ For $1, the simple interest for 1 year = 10/100

∴ For $3700, the simple interest in 1 year

= 10/100 × 3700

= 10 × 3700/100

= 37000/100 = $370

Thus, simple interest for 1 year = $370

Therefore, simple interest for 5 years

= Simple interest for 1 year × 5

= $370 × 5 = $1850

Thus, Simple Interest (SI) = $1850

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $3700 + $1850

= $5550

Thus, Amount to be paid = $5550 Answer


Similar Questions

(1) Anthony took a loan of $6600 at the rate of 9% simple interest per annum. If he paid an amount of $12540 to clear the loan, then find the time period of the loan.

(2) Mary took a loan of $4100 at the rate of 6% simple interest per annum. If he paid an amount of $6314 to clear the loan, then find the time period of the loan.

(3) Find the amount to be paid if Charles borrowed a sum of $5900 at 5% simple interest for 7 years.

(4) John took a loan of $4400 at the rate of 10% simple interest per annum. If he paid an amount of $7480 to clear the loan, then find the time period of the loan.

(5) Ashley had to pay $5096 in order to furnish the loan taken 3 years before. If the rate of simple interest was 4% then find the sum borrowed.

(6) Calculate the amount due if Barbara borrowed a sum of $3550 at 5% simple interest for 3 years.

(7) Calculate the amount due after 9 years if Linda borrowed a sum of $5350 at a rate of 6% simple interest.

(8) How much loan did Richard borrow 5 years ago at a rate of simple interest 2% per annum, if he paid $6160 to clear it?

(9) William had to pay $3815 in order to furnish the loan taken 3 years before. If the rate of simple interest was 3% then find the sum borrowed.

(10) Lisa had to pay $4536 in order to furnish the loan taken 3 years before. If the rate of simple interest was 4% then find the sum borrowed.


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