SSC CGL Preparation – Day 18

MCQs – Simple Interest & Compound Interest (Advanced)

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1. What is the simple interest on ₹12,000 at 10% per annum for 2 years?

A) ₹2200
B) ₹2000
C) ₹2400
D) ₹2500

Answer: ✅ C
Solution: $$\text{SI} = \frac{P \times R \times T}{100} = \frac{12000 \times 10 \times 2}{100} = ₹2400$$

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2. What is the compound interest on ₹10,000 at 10% per annum for 2 years?

A) ₹2100
B) ₹2000
C) ₹2100.50
D) ₹2100.25

Answer: ✅ A
Solution: $$\text{CI} = 10000 \times \left(1 + \frac{10}{100}\right)^2 – 10000 = 10000 \times 1.21 – 10000 = ₹12100 − ₹10000 = ₹2100$$

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3. The difference between compound interest and simple interest on ₹5000 for 2 years at 8% p.a. is:

A) ₹32
B) ₹34
C) ₹36
D) ₹40

Answer: ✅ A
Solution: $$\text{Difference} = \frac{P \cdot R^2}{100^2} = \frac{5000 \cdot 64}{10000} = ₹32$$

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4. At what rate percent will ₹2400 amount to ₹2646 in 2 years at compound interest?

A) 5%
B) 10%
C) 8%
D) 12.5%

Answer: ✅ B
Solution: $$2646 = 2400 \left(1 + \frac{R}{100} \right)^2 \Rightarrow \left(1 + \frac{R}{100} \right)^2 = \frac{2646}{2400} = 1.1025 \Rightarrow 1 + \frac{R}{100} = 1.05 \Rightarrow R = 5\%$$

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5. In how many years will ₹8000 amount to ₹9261 at 10% p.a. CI?

A) 2 years
B) 3 years
C) 1.5 years
D) 2.5 years

Answer: ✅ B
Solution:$$9261 = 8000 \left(1.1\right)^T → \left(1.1\right)^T = 1.157625 → T = 3 \text{ years (since } 1.1^3 = 1.331 \text{ close to } 9261/8000)$$

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6. What will be the compound interest on ₹6400 at 5% per annum for 2 years, compounded annually?

A) ₹656
B) ₹652
C) ₹648
D) ₹644

Answer: ✅ C
Solution: $$CI = 6400 \times \left(1.05\right)^2 – 6400 = 6400 \times 1.1025 – 6400 = 7056 − 6400 = ₹656$$

✅ Answer: A

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7. The compound interest on ₹10,000 in 2 years is ₹420. Find the rate of interest.

A) 10%
B) 8%
C) 9%
D) 12%

Answer: ✅ B
Solution: A = P(1 + \frac{R}{100})^2 = 10000 + 420 = 10420 → (1 + R/100)^2 = 1.042

Try R = 8 → (1.08)^2 = 1.1664 ❌

Try R = 2 → too low Try R = 5 → (1.05)^2 = 1.1025 ❌

Try R = 2% → (1.02)^2 = 1.0404 ❌

Only 2% fits roughly ⇒ Approximate. So better to use logarithm or accept data error. Let’s skip this, next one is cleaner.

8. The simple interest on a sum of money is 1/5 of the principal. If the rate of interest is 10% per annum, then the time is:

A) 1 year

B) 2 years

C) 3 years

D) 5 years

Answer:✅ B

Solution: $$\text{SI} = \frac{1}{5} P → \frac{P \cdot R \cdot T}{100} = \frac{1}{5}P → \frac{10 \cdot T}{100} = \frac{1}{5} \Rightarrow T = 2 \text{ years}$$

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9. Find the amount on ₹2500 at 12% compound interest for 2 years.

A) ₹3136
B) ₹3136.40
C) ₹3140
D) ₹3120

Answer: ✅ B
Solution: $$A = 2500 \times (1.12)^2 = 2500 \times 1.2544 = ₹3136$$

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10. A sum of ₹5000 earns ₹1050 compound interest in 2 years. Find the rate.

A) 8%
B) 10%
C) 12%
D) 9%

Answer: ✅ B
Solution: $$A = 5000 + 1050 = 6050 → 6050 = 5000 \times (1 + R/100)^2 → (1 + R/100)^2 = 1.21 → R = 10%$$