The cost of a stove to a store owner was $500, and she sold the stove for $1080. What was her percent of profit based on cost?

There are 15 plates and each plate is either 7 or 12 inches diameter. which systems of equations do you use to find the number of 7 inch plates, x and 12 inch plates, y

In a small section of a stadium there are 40 spectators watching a game between the cook islands and fiji. they all support at least one of the two teams. 25 spectators support the cook islands and 16 of these support both teams. how many support only fiji?

What is the gcf of 20c^3-5c^4+30c^6