Algebra
posted by Chuck .
Chuck and Dana agree to meet in Chicago for the weekend. Chuck travels 236 miles in the same time that Dana travels 224 miles. If Chuck’s rate of travel is 3 mph more than Dana’s, and they travel the same length of time, at what speed does Chuck travel?

r mi/h = Dana's rate.
r * t = 224 miles.
t = 224/r.
3)224r+3) mi/h = Chuck's rate.
(r+3)t = 236
Replace t with 224/r:
(r+3)224/r = 236
Multiply both sides by r:
(r+3)224 = 236r
224r + 672 = 236r
236r  224r = 672
12r = 672
r = 56 mi/h = Dana's speed.
r+3 = 59 mi/h = Chuck's speed. 
Correction: Chuck's rate = (r+3)mi/h.