Celia runs twice as fast as Lexie. If it takes Lexie 20 minutes to run a mile, how long, in minutes, will it take Celia to 30 miles?
If Lexie takes 20 minutes to run a mile, Celia takes 20/2 = <<20/2=10>>10 minutes to run the same distance since she is twice as fast.
Celia takes 10 minutes to run one mile so it will take 10*30 = <<10*30=300>>300 minutes to run 30 miles.
#### 300