math
posted by briana .
A stationery retailer generally prices portable computers using a 30 percent markup. The retailer expects to sell 100 portable computers at the 30 percent markup. How many units would it have to sell at a 10 percent increase in price from the original price to maintain the same gross profit?

Let the original cost price be 1000.
100 computers at 30% markup brings a profit of 100*(1000*30%)=30000
If the original price goes up 10% (cost =1100), the new profit per computer is 13001100=200
Number computers required to maintain the same total profit
= 30000/200=150