Multiple choice general knowledge math & puzzles

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 ?

  1. 2010

  2. 2011

  3. 2012

  4. 2013

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let n be the years after 2001. Price X = 420 + 40n. Price Y = 630 + 15n. We want X = Y + 40. So, 420 + 40n = 630 + 15n + 40. 25n = 250, so n = 10. 2001 + 10 = 2011.