Explanation : C.P. of 2 pens = 740. Let C.P. of 1st pen be x
and C.P. of 2nd pen be y.
Since there is no profit and loss in the whole transaction, so 12% of x = 8% of y
⇒ x : y = 2 : 3
Hence the cost of first pen = (2/3) × 740 = Rs 296 and
that of the second pen = (3/5) × 740 = Rs 444.