The price of commodity P increases by 40 paise every year, while the price of commodity Q increases by 15 paise every year. If in 2001, the price of commodity P was Rs. 4.20 and that of Q was Rs. 6.30, in which year commodity P will cost 40 paise more than the commodity Q ?	Pick one.
A) 2008
B) 2009
C) 2010
D) 2011
E) 2012
Let the commodity P costs 40 paise more than the commodity Q after n years.   Price of the commodity P in 2001 = Rs.4.20   Since the price of the commodity P increases by Rs 0.40 every year,   Price of the commodity P after n years from 2001 = Rs.4.20 + (n × .40)   Price of the commodity Q in 2001 = Rs.6.30   Since the price of the commodity Q increases by Rs 0.15 every year,   price of the commodity Q after n years from 2001 = Rs.6.30 + (n × .15)   Since the commodity P costs Rs. 0.40 more that the commodity Q after n years from 2001,   4.20 + (n × .40) = 6.30 + (n × .15) + 0.40   =&gt; (40n - .15n) = 6.30 - 4.20 + 0.40= 
<gadget id="calculator">6.30 - 4.20 + 0.40</gadget>
<output>2.5</output>
2.5=&gt; .25n = 2.5   =&gt; n =2.5/.25= 
<gadget id="calculator">2.5/.25</gadget>
<output>10</output>
10=&gt; Commodity P costs Rs.0.40 more that the commodity Q after 10 years from 2001.   i.e., in 2011   ANSWER:2011
<result>D</result>
The price of commodity P increases by 40 paise every year, while the price of commodity Q increases by 15 paise every year. If in 2001, the price of commodity P was Rs. 4.20 and that of Q was Rs. 6.30, in which year commodity P will cost 40 paise more than the commodity Q ?