Terrance and Jessie are training for long-distance race Terrance trains at a rate of 6 miles every half hour and Jesse trains at a rate of 2 miles every 15 minutes what is the unit rate in miles per hour for each Runner

There are several information's already given in the question. Based on those information's the answer can be easily deduced.

Distance covered by Terrance in 1/2 hour = 6 miles

So

Distance covered by Terrance in 1 hour = 6 * 2 miles

= 12 miles

So the unit rate of Terrance is 12 miles per hour.

Now

Distance covered by Jessie in 1/4 hour or 15 minutes = 2 miles

Then

Distance covered by Jessie in 1 hour = 2 * 4 miles

= 8 miles

Then the unit rate of Jessie is 8 miles per hour.