A man purchases 8 pens for Rs.9 and sells 9 pens for Rs.8, how much profit or loss does he make?
Options:
(A) 15
(B) 66
(C) 88
(D) 1
(E) 12 OK. Let's think. Some random thoughts first:
90 * 10/60 = 15 kmph The answer: (A).