Simple Interest
MCQs Math


Question:     Calculate the amount due if Sarah borrowed a sum of $3850 at 2% simple interest for 4 years.


Correct Answer  $4158

Solution And Explanation

Solution

Given,

Principal (P) = $3850

Rate of Simple Interest (SI) = 2%

Time (t) = 4 years

Thus, Amount (A) = ?

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

Thus, here 2% simple interest means, Rate of Simple Interest (SI) is 2% 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 × 2% × 4

= $3850 ×2/100 × 4

= 3850 × 2 × 4/100

= 7700 × 4/100

= 30800/100

= $308

Thus, Simple Interest = $308

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 + $308

= $4158

Thus, Amount to be paid = $4158 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) = 2%

And, Time (t) = 4 years

Thus, Amount (A)

= $3850 + ($3850 × 2% × 4)

= $3850 + ($3850 ×2/100 × 4)

= $3850 + (3850 × 2 × 4/100)

= $3850 + (7700 × 4/100)

= $3850 + (30800/100)

= $3850 + $308 = $4158

Thus, Amount (A) to be paid = $4158 Answer

Method (3) Unitary Method

Calculation of Amount using Unitary Method

Calculation of Interest using Unitary Method

Here, given Rate of Simple Interest = 2%

This, means, $2 per $100 per year

∵ For $100, the simple interest for 1 year = $2

∴ For $1, the simple interest for 1 year = 2/100

∴ For $3850, the simple interest in 1 year

= 2/100 × 3850

= 2 × 3850/100

= 7700/100 = $77

Thus, simple interest for 1 year = $77

Therefore, simple interest for 4 years

= Simple interest for 1 year × 4

= $77 × 4 = $308

Thus, Simple Interest (SI) = $308

Calculation of Amount

Amount = Principal + Interest

Thus, Amount = $3850 + $308

= $4158

Thus, Amount to be paid = $4158 Answer


Similar Questions

(1) Patricia took a loan of $4300 at the rate of 8% simple interest per annum. If he paid an amount of $7052 to clear the loan, then find the time period of the loan.

(2) What amount does Thomas have to pay after 5 years if he takes a loan of $3800 at 8% simple interest?

(3) What amount does Michael have to pay after 5 years if he takes a loan of $3300 at 3% simple interest?

(4) What amount does Elizabeth have to pay after 6 years if he takes a loan of $3450 at 9% simple interest?

(5) Joseph took a loan of $5400 at the rate of 6% simple interest per annum. If he paid an amount of $7344 to clear the loan, then find the time period of the loan.

(6) If Barbara paid $4260 to settle his loan which he had taken 4 years before at a simple interest of 5%, then find the loan taken.

(7) If Joshua paid $5488 to settle his loan which he had taken 4 years before at a simple interest of 3%, then find the loan taken.

(8) Calculate the amount due if James borrowed a sum of $3000 at 5% simple interest for 4 years.

(9) Sarah took a loan of $5700 at the rate of 10% simple interest per annum. If he paid an amount of $10830 to clear the loan, then find the time period of the loan.

(10) Sandra took a loan of $6900 at the rate of 6% simple interest per annum. If he paid an amount of $9384 to clear the loan, then find the time period of the loan.


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