Simple Interest
MCQs Math


Question:     Christopher took a loan of $6000 at the rate of 10% simple interest per annum. If he paid an amount of $9600 to clear the loan, then find the time period of the loan.


Correct Answer  6

Solution And Explanation

Solution

Given,

Principal (P) = $6000

Rate of Simple Interest (R) = 10% per annum

Amount (A) = $9600

Thus, time (T) = ?

Method (1) Using Formula

Calculation of Simple Interest, when Principal and Amount are given

Formual to Calculate Simple Interest when Principal and Amount are given

We know that, Amount (A) = Principal (P) + Simple Interest (SI)

⇒ Simple Interest (SI) = Amount – Principal

⇒ SI = $9600 – $6000 = $3600

Thus, Simple Interest = $3600

Calculation of the Time using forumula when Amount, Simple Interest and Principal are known

Formula to find the Time (T)

Time (T) = 100 × Simple Interest/Principal × Rate of Interest

⇒ T = 100 × SI/P × R

Thus, Time (T) = 100 × 3600/6000 × 10

= 360000/60000

= 6 years (using formula)

Thus, Time (T) = 6 years (from time taken before calculation)Answer

Calculation of the Time using Unitary Method when Amount, Simple Interest and Principal are known

Here, we have

Principal (P) = $6000

Rate of Simple Interest (R) = 10% per annum

Simple Interest = $3600 (As calculated above by subtracting Principal from the Amount given)

We know that, interest is calculated on the basis of the Principal.

This means Simple Interest for 1 year = Rate of simple interest × Principal

Thus, Simple Interest for 1 year = 10% of Principal

= 10% of $6000

= 10/100 × 6000

= 10 × 6000/100

= 60000/100 = 600

Thus, simple Interest for 1 year = $600

Now,

∵ If the simple Interest is $600, then the time = 1 year

∴ If the simple Interest is $1, then the time = 1/600 years

∴ If the simple Interest is $3600, then the time = 1/600 × 3600 years

= 1 × 3600/600 years

= 3600/600 = 6 years

Thus, time (T) = 6 years Answer


Similar Questions

(1) What amount will be due after 2 years if John borrowed a sum of $3100 at a 6% simple interest?

(2) What amount does David have to pay after 5 years if he takes a loan of $3400 at 7% simple interest?

(3) In how much time a principal of $3150 will amount to $3276 at a simple interest of 2% per annum?

(4) Calculate the amount due if Linda borrowed a sum of $3350 at 10% simple interest for 4 years.

(5) What amount does Patricia have to pay after 5 years if he takes a loan of $3150 at 5% simple interest?

(6) What amount does David have to pay after 5 years if he takes a loan of $3400 at 8% simple interest?

(7) Mark took a loan of $6800 at the rate of 8% simple interest per annum. If he paid an amount of $10064 to clear the loan, then find the time period of the loan.

(8) Calculate the amount due if John borrowed a sum of $3200 at 5% simple interest for 3 years.

(9) Find the amount to be paid if Thomas borrowed a sum of $5800 at 3% simple interest for 8 years.

(10) Joseph took a loan of $5400 at the rate of 9% simple interest per annum. If he paid an amount of $9774 to clear the loan, then find the time period of the loan.


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