-at 6am 2 planes started from the same airport and flew west. on plane averaged 520 mph and the other 600 mph at what time were the planes 280miles apart?
and
- a at 9 am 2 cars started from the same town and traveled northon the same road. one car avereged 45 mph and the othe 40 mph, in how many hours were the cars 30 miles apart.
PLEASE EXPLAIN!!!!!!!!!!!!
2006-10-09 05:20:18 · 4 answers · asked by hazel 2 in Education & Reference ➔ Homework Help
d=rt
d1-d2 = (r1-r2)t
From the problem statement we know that d1-d2 = 280
r1=600 r2=520
r1-r2=80
solve for t
280/80 = t
=3.5 hours
9:30 AM
the second problem is solved the same way:
d1-d2=30
r1-r2=5
t=6 hours
which would be 3PM
j
2006-10-09 05:25:16 · answer #1 · answered by odu83 7 · 0⤊ 0⤋
d = vt
Distance = Velocity (speed) multiplied by Time
One plane traveled some distance d. Another plane traveled at some distance (d + 280). You can set up two equations with two unknowns (d and t, you already know v from the problem).
Same idea with the second question.
Show us work and we can try to point out where you might be going wrong.
Ah, forget it. Just wait a few minutes and you'll get your answer. Too many desperate people pining for those precious 10 points.
2006-10-09 12:28:21 · answer #2 · answered by J C 3 · 0⤊ 0⤋
1. Find out how far apart each plane is after each hour.
600-520 = 80. The planes are flying 80 miles apart per hour. 280 / 80 = 3.5 hours. 6am plus 3.5 hours is 9:30am.
2. Solve like the first one
2006-10-09 12:29:35 · answer #3 · answered by msbedouin 4 · 0⤊ 0⤋
Remember D=RT. Distance = rate x time
2006-10-09 12:24:03 · answer #4 · answered by nmtgirl 5 · 0⤊ 0⤋