Test: SI & CI - CAT MCQ

The annual interest would be Rs. 60. After 3 years the total value would be 1200 + 60 x 3 = 1380

2100 + 5% of 2100 = 2100 + 105 = 2205 (after 1 year). Next year it would become: 2205 + 5% of 2205 = 2205 +110.25 = 2315.25

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 = Rs. 5

8% of 800 for 4 years + 6% of 800 for 4 years = 64 x 4 + 48 x 4 = 256 + 192 = 448. However, we do not know the rate of interest applicable in the 5 th year and hence cannot determine the exact simple interest for 9 years.

Let's solve this step by step:

Understanding the problem:

• We need to find the principal amount.
• The rate of interest is 16 2/3% per annum, which is equivalent to 50/3%.
• The time period is 2 years.
• The final amount (principal + interest) is Rs. 196.

Formula for compound interest:

• Amount (A) = Principal (P) * (1 + Rate/100)^Time

Substituting the values:

• 196 = P * (1 + 50/300)^2
• 196 = P * (7/6)^2
• 196 = P * 49/36

Solving for Principal (P):

• P = 196 * 36 / 49
• P = 144

Therefore, the principal amount is Rs. 144.

So, the correct answer is option 4: Rs. 144.

For the last 5 years, the interest earned would be: 30% of 360 = 108. Thus, interest earned in the first 4 years would be Rs. 72 → Rs. 18 every year on an amount of Rs. 360- which means that the rate of interest is 5%

The average rate of interest he pays is 186 x 100/1500 = 12.4%.

The average rate of interest being 12.4%, it means that the ratio in which the two amounts would be distributed would be 4:1 (using alligation). Thus, the borrowing at 12% would be Rs. 1200.

The data is insufficient as we do not know the time period involved.

The difference would amount to 8% of the value borrowed. Thus 56 = 0.08 x sum borrowed in each case → Sum borrowed = Rs. 700.

Interest per year = Rs. 25. Thus, an interest of Rs. 50 would be earned in 2 years.

Solve using options. If we try 500 (option b) for convenience, we can see that the difference between the two is Rs. 64 (as the SI would amount to 300 and Cl would amount to 100 + 120 + 144 = 364). Since, we need a difference of only Rs. 48 we can realize that the value should be 3/4th of 500. Hence, 375 is correct.