How do you find the amount to mark up or discount by
% increase or decrease x original price
How do you find the % mark up or discount
Change in price
Original price x100
How do you find the profit
Selling price - cost
How do you find the loss
Cost - selling price
How do you find the % profit or loss
Profit or loss
Cost price x100
How to find the new price
(100% + r%) x old price
How do you find the old price
new price
100% + r%