solve the word problem

Question

bill starts out on his daily run at 8am and Sue rides out at 9:30 am to catch up with him on her bike . if bill rune at 8 miles per hour and Sue pedals at 20 miles per hour, at what time will Sue catch up to Bill?

Answer 1

So, d = rt, right? Once they meet, they will have travelled the same distance.

 

If Sue's time is t, then Bill's is t + 1.5, because he left 1 1/2 hours earlier.

 

8(t + 1.5) = 20t

8t + 12 = 20t

12t = 12

t = 1

 

So, they meet up at 10:30.

 

Is this correct? In one hour, Sue has gone 20 miles. By then, Bill has gone 8(2.5) = 20 miles. Ding ding ding!