Little Johhny walks to school from home at 4 mph, and returns home at 4k mph. If the total traveling time is t, what is the total distance d covered by Little Johnny?
2006-09-28 08:07:31 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
4k NOT 4 mph.
2006-09-29 07:14:20 · update #1
speed to school=4mph=6.4kmph
average speed=6.4+4 / 2=5.2kmph
distance=5.2t km.
2006-09-28 08:11:16 · answer #1 · answered by raj 7 · 0⤊ 0⤋
The expression "4k mph" is a little confusing, but if I assume it is a slip of the finger and is meant to be "4mph" (but, remember, slips of the finger just are not acceptable for mathematicians), ie he walks to and from school at the same speed (and it is quite a speed for someone with such short legs), then using the fact that distance = speed x time, the there-and-back distance d is simply 4t miles, where of course t must be in hours, or if you want the one way distance it is 2t miles. I can't help feeling I've missed something here! Sorry if I haven't helped.
2006-09-28 15:25:01 · answer #2 · answered by Sangmo 5 · 0⤊ 0⤋
do you need it in kmph or mph?
rate*time=distance
there are 1.6km in a mile
4mph*t+(4kmph)(1mph/1.6kmph)t
(the kmph cancel to give you mph)
4mph*t+2.5mph*t
6.5mph*t would be the distance in miles
(1.6kmph/1mph)(6.5mph*t) -------> the mph cancel to give you:
10.4kmph*t would be the distance in km
2006-09-28 15:25:38 · answer #3 · answered by Anonymous · 0⤊ 0⤋