Test Level 1: Simple & Compound Interest - 1 - CAT MCQ

Simple interest = 
Profit earned by Mr. Bajaj = SI received by Mr. Bajaj from Ambani + SI received by Mr. Bajaj from Mittal - SI paid by Mr.Bajaj to the bank
= 1,000 + 2,250 - 3,000
= Rs. 250

The problem can be solved by using the formula for simple interest:

We need to put the value of each principle amount at a different rate of interest as each of them is invested for a year:
SI = Rs. 500
So, 
⇒ 50,000 = 20,000 + 14,000 + 2500x
⇒ 16,000 = 2500x
⇒ 
⇒ x = 6.4
This is correct answer. 

Suppose, Rs. x be lent at 6% and Rs. (4000 – x) at 8%.
Then,

6x + 32000 – 8x = 27200
2x = 32000 – 27200 = 4800
x = Rs. 2400
Thus, the two parts are Rs. 2400 and Rs. 1600.
So, required ratio = = 3 : 2

Let P be the principal.
Compound interest for 2 years = P 
Simple interest for 2 years =

Principle amount = Rs. 1500

Let for x years he paid at 7.5%.

⇒ (13,500x - 12,600x) + 2,64,600 = 2,70,900
⇒ 900x = 2,70,900 - 2,64,600
⇒ 900x = 6300

Let's consider the principal is Rs1400 and rate of interest is 10%.

then after 1st year the interest will be( Rs 1400 × 10% )= Rs140

After completing first year the principal amount will be :-

Principal + rate of interest = Rs ( 1400 + 140) =Rs 1540

In second the principal will be = Rs1540

Rate of interest will be same = 10%

Now after second year the interest will be :-

  1540 × = Rs154

∴ After second year total repaid amount will be:-

=Principal of second year + interest after second year .

=Rs( 1540 + 154) =Rs 1694

Hence option d) matches with the question,

Ans :- Only option (d) matches with the question. there option (d) will be the correct answer.

5% for 3 years (SI) = 15% of the amount; At the same time 4% SI for 4 years means 16% of the amount. The difference between the two is 1% of the amount. 1% of 500 = ₹ 5

The loan is taken for simple interest => Interest is always calculated on the initial principal amount and not on the outstanding amount.
=> The interest for each of the four years is the same, which is equal to = Rs 4000.
Interest for four years = 4 * 4000 = Rs 16000.
Total amount = 20000 + 16000 = Rs 36000
=> Each equal installment = 36000/4 = Rs 9000

Principal for first year = 10000, So interest for first year would be 10000*10/100 = 1000
Now for the remaining two years, the principal would be 7000, so interest that he will pay in 2 years = 7000*2*10/100 = 1400
Thus, the total interest that he ends up paying is 1400 + 1000 = 2400

Let the amount invested in first bank be x
So interest earned in 3 years = x*5*3/100 = .15x
Now amount invested in second scheme is 2x
So the amount after 3 years would be
(1.03)³ * 2x = 2.185x
So the interest earned = .185x
Thus the interest earned in second case is 24% more than the interest earned in first case.