You leave your house and walk for half an hour at a speed of 3 miles per hour. then you run for 15 minutes at a speed of 7 miles per hour. you are now halfway to town. write and solve an equation to find the distance from your house to town.

If you walk for half an hour at 3 mph, you will have walked 1.5 miles. 
If you run for 15 minutes at 7 mph, you will have ran 1.75 miles. 
These together is halfway, so the equation is 
2 x (1.5 + 1.75) = d 
Add 1.5 and 1.75 together. 
2 x 3.25 = d 
Multiply 2 by 3.25. 
6.5 = d 
It is 6.5 miles to town, hope this helps!