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
Let the total length of pencil = L cm Then, black part = L/8∴ Remaining part = L - L/8 = 7L/ 8 and White part = (7L/8)/2 = 7L/8∴ Remaining part = L - (L/8 + 7L/16) = 7L/16∴ length of blue part = 7L/16According to the question, 7L/16 = 31/2⇒ 7L/16 = 7/2 ∴ L =8