Constant Rate Revisited

Constant Rate and Review

Recall from yesterday:

• Any constant rate problem can be described by a linear equation where the slope of the graph is the constant rate.

Rate of Painting

• You paint 8 square feet in 2 minutes

•  $rate=\frac{8}{2}=4$  

• Slope of the graph:  $\frac{4}{1}=4$  

• y = 4x

Solar Panel:

• 240 watts in 2 hours

• rate= 120 watts per hour

• slope of the graph: also 120

• y = 120x

Unit rate is always the same as slope

Calculating the unit rate will give you the slope

Multiple Choice

How are unit rate and slope related?

• They are the same

• They are different

Open Ended

What is the unit rate for decorating 30 notebooks in 3 hours?

Multiple Choice

What is the slope of the line describing decorating 30 notebooks in 3 hours?

• 30

• 10

• 3

Unit rate situations:

• Wash 80 dishes in 20 minutes

• Unit rate and slope:

   $\frac{80}{20}=4$  dishes per minute

Unit rate situations:

• Paint 40 greeting cards in 2 hours

• Unit rate and slope:

   $\frac{40}{2}=20$  greeting cards per hour

Unit rate situations:

• Drive 300 miles in 6 hours

• Unit rate and slope:

   $\frac{300}{6}=50$  miles per hour

Unit rate situations:

• Knit 3 scarves in 3 days

• Unit rate and slope:

   $\frac{3}{3}=1$  scarf per day

In Summary:

• Any unit rate problem can be described by a linear equation where the slope of the graph is the unit rate.

• Unit rate is always the same as slope!