On what sum of money will the difference between SI and CI for 2 years at 5% pa be equal to Rs 63?

Directions: Read the following questions carefully and answer them:

If P is the principal amount and the rate of interest is r% per annum and the compound interest is calculated k times in a year, the what is the amount at the end of n yr?

» Explain it

Correct Option: A

Given, principal amount = ₹ P

and Time, t = nk

Hence, option A is correct.

An amount of Rs. X at compound interest at 20% per annum for 3 year becomes y. what is y : x?

» Explain it

Correct Option: C

Let P = ₹ x,  r = 20%,  t = 3 year,  A = ₹ y

∴   y : x  = 216 : 125.

Hence, option C is correct.

What is the least number of complete year in which a sum of money at 20% compound interest will be more than doubled?

» Explain it

Correct Option: D

Method I:

Let the sum of money = ₹ P

∴  Amount = 2P

On putting t = 4, we get

∴  Least number of year = 4.

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Method II: 

A sum will get double of itself at an overall interest rate of 100%

Let's apply the net% effect formula to get to know how many years would it take for interest to go beyond 100%

Here, we can see that in 4 yrs the given compound rate of interest is occuring to more than 100%.
Therefore, 4 yrs is the correct answer.

Hence, option D is correct.

What is the compound interest on Rs. 1600 at 25% per annum of 2 year compounded annually?

» Explain it

Correct Option: D

To solve this question we can apply a short trick approach

P = ₹ 1600, r = 25% and n = 2 year

By the short trick approach, we get

	Principal		Compound Interest
100		56.25
1600		x

By the cross multiplication, we get

Hence, option D is correct.

On what sum of money will the difference between simple interest and compound interest for 2 years at 5% pa be equal to Rs. 63?

» Explain it

Correct Option: A

Method I:

To solve this question, we can apply a short trick approach

Given,

Difference = 63,    r = 5%

By the short trick approach, we get

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Method II:

We can solve it by the net% effect formula,

Rate % of SI for 2 yr at 5% pa = 5 × 2 = 10%

Rate % of CI for 2 yr at 5% pa

% rate difference of CI and SI = 10.25% – 10% = .25%

Let the sum be x, then

0.25% of x = 63

Hence, option A is correct.

On what sum of money will the difference between SI and CI for 2 years at 5 per annum be equal to 25?

On what sum of money will CI for 2 years at 5% a year to Rs 164?

What is the formula of difference between CI and SI for 2 years?

On what sum of money will the difference between simple interest and compound interest for 2 years at 5% per annum?