Can someone please help me with this easy math problem

The holiday party will cost $160 if 8 people attend.if there are 40 people who attend the party, how much will the holiday party cost

We have 339 ounces of jam to be divided up equally for 12 people how muny ounces will each person get

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?