Discussion Forum

The price of commodity X increases by 40 paise every year, while the price of commodity Y increases by 15 paise every year. If in 2001, the price of commodity X was Rs. 4.20 and that of Y was Rs. 6.30, in which year commodity X will cost 40 paise more than the commodity Y ?

Answer:

Explanation:

Suppose commodity X will cost 40 paise more than Y after z years .Then,
(4.20+0.40z)-(6.20+0.15z) = 0.40
=> 0.25z = 0.4+2.10 => z = 250/0.25 = 250/25 = 10
X will cost 40 paise more than Y ,10 years after 2001 ie in 2011.