Answer: Robert and Chris can skate 10 miles in 45 minutes.
Step-by-step explanation:
Let's start by finding the unit rate.
[tex]\frac{4}{18} =\frac{2}{9} \\\frac{18}{18} =1[/tex]
Robert and Chris can skate [tex]\frac{2}{9}[/tex] of a mile in 1 minute. Now we can multiply both by 45 to see how far the can go in 45 minutes.
[tex](\frac{2}{9}) (\frac{45}{1} )\\\frac{(2)(45)}{(9)(1)} \\\frac{90}{9} \\10[/tex]
45x1=45
The can skate 10 miles in 45 minutes.
