Q. In what time will 1860 Rs. amount to 2641.20 at simple interest 12% per annum ?
Answer: 3.5 year
Notes: SI = 2641.20 - 1860 = 781.2 Rs. $latex Time = \frac{SI\times 100}{Princ.\times Rate}&s=1$ $latex = \frac{781.2\times 100}{1860\times 12} = 3.5 = 3\frac{1}{2}\ years&s=1$ Hence option [B] is correct answer.

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