Recognising and representing proportional relationships between quantities

Mark's Plumbing charges $45 per hour plus a service fee of $80 for coming out to your house. Which equation models this situation?

• y = 45x - 80

• y = 80x + 45

• y = 45x + 80

• y = 80x - 45

• A

• B

• C

• D

The equation y = 1/2x represents the cost y for the number of x meals. How many meals can be bought with $40?

• 80 meals

• 20 meals

• 10 meals

• 40 meals

What is the percent equation for "Find the Whole" and "3 is 50% of what number?"

• 3/50 = n/100

• p/3 = 50/100

• 3 = 0.5 * w

• 3 = n * 0.5

• p = 0.5 * 3

What is the formula for a proportional relationship?

• y=kx
• y=k/x
• z=ykx
• y=ky

Solve for the following proportion using cross multiplication

• x=8

• x=7

• x=9

• x=10

What does k represent in the equation y = kx?

• konkrete kids
• constant of proportionality
• kangaroos
• krispy kreme

Write an equation for this situation.

• k=19.25x
• y=19x
• y=19.25x
• y=9.5x

Which of the following is the correct set up of the proportion in this problem:

"Thirty-six is 30% of what number?"

The percent proportion looks like: