Tali jogs a mile in 12 minutes. How many miles per hour is Tali running?

Sandra runs twice as fast as Tali. How many miles per hour is Sandra running? How long does it take for Sandra to run a mile?

Tali is running at 5 miles per hour. In 12 minutes she runs 1 mile, in 1 minute she runs 1/12 mile, so in 60 minutes (one hour) she would run 60/12 = 5 mph Sandra is running at 10 miles per hour, this is twice as fast as Tali (5 mph x 2 = 10 mph). It takes Sandra 6 minutes to run a mile. Sandra runs 10 miles in an hour, so to run one mile would take her one tenth of an hour or 6 minutes.