The ratio x : y is equal to 2 : 5, and y is 80% of z. Write an equation to represent the proportional relationship between x and z.

How do you solve a question like this?

You receive 15% of the profit from a car wash how much money do you receive from a profit of 300

The number of 8th graders who responded to a poll of 6th grade and 8 th graders was one fourtg of the number of 6th graders whi responded if a total of 100 students responddd to the poll how many of the students responded were 6 th graders