Math question F.1

1) A man sells two machines at $20000 each.He makes a profit of 20%on one
machine , and suffers a loss of 30% on the other. Find his loss percentage on the whole.

2) The mareed price of a mobile phone is $900. If there is a discount of 25%,how much can a customer save?

3) Since there is a discount of 15%, a man saves $96 in buying a tent.
a) Find the marked prince of the tent.

b) Find the selling price of the tent.

c) if the owner markes a profit of 36%, find the cost of the tent.