F.1 Eng math 10 point

1, 270 = X(1-10%) Let X be the cost
X = 300
Y = 300(1+20%) Let Y be the selling price
Y = 360

2, X (1+40%)*(1-20%) = 1120 Let X be the cost
X(1.4)(0.8) = 1120
X = 1000

F.1 Eng math 10 point
1.When a certain product is sold at $270, the loss made is 10%. If the product is sold for a profit of 20%, find the selling price.

2.A coat is marked at a price 40% higher than the coat. It is then sold at a discount of 20%. If the selling price is $1120, what is its cost?

　以上問題只要式以及答案...thx

A:
1, Let X be the cost
X = 300
Y = 300(1+20%) Let Y be the selling price
Y = 360

2, 1120 Let X be the cost
X(1.4)(0.8) = 1120
X = 1000