Converting the given fractions into decimal form, we have,8/9 = 0.8818/23 = 0.7816/21 = 0.7614/17 = 0.82From the above, 0.88 is the largest.Corresponding fraction is 8/9.
Suppose commodity X wil cost 40 paise more than Y after Z years.Then, (4.20 + 0.40Z) - (6.30 + 0.15Z) = 0.40 0.25Z = 0.40 + 2.10 Z= X will cost 40 paise more than Y 10 years after 2001 . i.e in 2011