Rosie runs 6 miles per hour. She runs for 1 hour on Monday, 30 minutes on Tuesday, 1 hour on Wednesday, and 20 minutes on Thursday. If she wants to run 20 miles for the week, how many minutes should she run on Friday?
How many miles does Rosie run on Monday and Wednesday? ** On Monday and Wednesday, Rosie runs 6*1= <<6*1=6>>6 miles.
How many miles does Rosie run on Tuesday? ** On Tuesday, Rosie runs 6*(30 minutes/60 minutes) = <<6*(30/60)=3>>3 miles.
How many miles does Rosie run on Thursday? ** On Thursday, Rosie runs 6*(20 minutes/60 minutes)=<<6*(20/60)=2>>2 miles.
How many miles has Rosie run so far this week? ** So far this week Rosie has run 6+3+6+2=<<6+3+6+2=17>>17 miles.
How many miles must Rosie run on Friday? ** To reach her goal, she must run 20-17=<<20-17=3>>3 miles on Friday.
How many minutes should Rosie run on Friday? ** Thus, she should run for 6/3=.5 hour which is 30 minutes.
#### 30