Applying Proportional Relationships

Applying Proportional Relationships

What we need to remember:

• in an ordered pair, the coordinates are always (x, y)

• a proportional relationship equation is always in the form y = kx

• to find k, the constant, you will always do

   $\frac{y}{x}\ which\ means\ y\div x$ 

Multiple Select

Amelia needs to buy some cat food. At the nearest store, 2 bags of cat food cost $5.50. How much would Amelia spend on 6 bags of cat food?

How should this be set-up to solve for it?

• $\frac{money}{bags}=\frac{5.5}{2}=x\ \ \ per\ \ \ \ bag;\ then\ \ x\times6$

• $\frac{money\ }{bags}=\frac{5.5}{2}=\frac{x}{6}$

• $\frac{money}{bags}=\frac{5.5}{2}=x$

• $\frac{money}{bags}=\frac{6}{5.5}=\frac{x}{1}$

Multiple Choice

Emily goes to a hardware store to buy wire. The table shows the cost, y, in dollars for x inches of wire she needs.

Emily needs 23 feet of wire. How much will it cost her?

^{Hint: 12 inches = 1 foot}

• $1.84

• $0.08

• $22.08

• $12.50