MATHS...simultaneous equation

1. A retailer bought a number of glasses for a total cost of $48. Two of the
glasses were broken accidentally in the store. However, by selling each of the
remaining glasses at $3 more than the original cost, the retailer could still make a total profit of $22.

(a)How many glasses did the retailer buy?
(b)What was the selling price of each glass?

ANS is (a)12 glasses (b)$7

2. A shopkeeper bought a number of glassware for a total cost of $3600.In the
frist week, he sold 60 pieces, each one at o price of $18 more than its original
cost.

After that,12 pieces were broken accidentally. In the second week, he sold all
the remaining glassware , each piece at a price of $6 less than its original cost.
On the whole , he could still make a profit of $480. What was the original cost
or each Piece of glassware?

ANS is $36


THX!!!