A man travels 1/4 distance from Colorado to Denver at 40mph and then goes the rest of the way at 65 mph. What is his average speed?
PS i KNOW the answer (56.667)..about.. so PLEASE show me the WORK!! thanks
i tutored some kid and i cant believe i forgot how to do thisss
2007-11-09 11:38:43 · 2 answers · asked by gotmilky2001 2 in Education & Reference ➔ Homework Help
Denver is in Colorado, so if this is a joke, that's the answer.
Assuming this is a math problem:
Let 4d equal the distance to Denver (using 4d simplifies the fractions).
He travels 1d miles at 40mph, so it takes 1d/40 hrs.
Then he travels 3d miles at 65mph, so it takes 3d/65 hrs
Altogether it takes (1/40 + 3/65)d hrs to travel the distance.
1/40 + 3/65 = (13 + 24)/520 = 37d/520 hrs
The total distance is 4d.
4d / (37d/520) = 4d*520 / 37d = 56.2 mph
2007-11-09 11:58:33 · answer #1 · answered by Steve A 7 · 0⤊ 0⤋
40+(65x3)=235
235/4=58.75
2007-11-09 19:45:02 · answer #2 · answered by violingirl7777 3 · 0⤊ 1⤋