Question

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 $Y$?

• A. 2010
• B. 2011
• C. 2012
• D. 2013

Answer 1

The correct option is B 2011

Suppose commodity $X$ will cost $40$ paise more than $Y$ after $z$ years.

Then, $(4.20+0.40z)-(6.30+0.15z)=0.40$

$\Rightarrow 0.25z=0.40+2.10$

$\Rightarrow z=\frac{2.50}{0.25}=\frac{250}{25}=10$.

$\therefore$ $X$ will cost $40$ paise more than $Y$ $10$ years after $2001$ which is $2011$.