The banker's discount on a sum of money for 3 years is Rs. 1116. The true discount on the same sum for 4 years is Rs. 1200. What is the rate per cent?	Choose the correct choice from the following choices:
A) 8%	B) 12%	C) 10%	D) 6%	E) 7%
Explanation :   BD for 3 years = Rs. 1116   BD for 4 years = 11163 × 4 = Rs. 1488   TD for 4 years = Rs. 1200   F = BD × TD(BD – TD) = (1488 × 1200)/(1488–1200) = (1488×1200)/288   = (124 × 1200)/24 = (124 × 100)/2 = 62 × 100 = Rs. 6200   =&gt; Rs.1488 is the simple interest on Rs. 6200 for 4 years   ⇒ 1488 = (6200 × 4 × R)/100   ⇒ R = (1488 × 100)/(6200 × 4)   = (372 × 100)/6200 = 372/62= 
<gadget id="calculator">372/62</gadget>
<output>6</output>
6% Answer : Option 6%
<result>D</result>
The banker's discount on a sum of money for 3 years is Rs. 1116. The true discount on the same sum for 4 years is Rs. 1200. What is the rate per cent?