A sum amounts to Rs.18,600 after 3 years and to Rs. 27,900 after 6 years, at a certain rate percent p.a., when the interest is compounded annually. The sum is:
Show answer & explanation
Correct answer: B
Explanation
Correct Answer is option 2 i.e. 12,400
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Concept |
Understanding |
Application |
Fair calculation |
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A = P[1 + r/100]t |
Suppose Sum = P A (After 3 years) = Rs. 18600 A (After 6 years) = Rs. 27900
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Since the duration is same: ⇒ 18600/x = 27900/18600 ⇒ x = (18600 × 18600)/27900 ⇒ x = 12400 |
x = (18600 × 18600)/27900 = 18600 × 62/93 = 18600 × 2/3 = 6200 × 2 = 12400 |