Find the percent decreased original price: $40 sale price: $30

25 percent

Step-by-step explanation:

Percent decrease = (original - new)/original * 100 percent

                              = (40-30)/40 * 100 percent

                              = 10/40 * 100 percent

                              = .25 * 100 percent

                               =25 %

c

step-by-step explanation:

the ratio of balloons to tables is 5: 2 and the constant variation is 5.

the equation is y=5x