Here's what you need to memorize for your exam tomorrow.
Distance = (speed) x (time) .
That's it. Memorize it.
-- If the question wants you to find speed, use it exactly in that form.
-- If the question wants you to find speed, then divide each side by (time)
and it says
. Time = (distance) / (speed) .
-- If the question wants you to find time, then divide each side by speed,
and it says
. Time = (distance) / (speed) .
So if you memorize that one equation ... Distance = (speed) x (time) ...
you can solve ANY problem to find distance, speed, or time.
On the sheet in the picture . . . . .
#2). The question is "How long ?". That's TIME that you have to find.
Use the equation in the form of
. TIME = (distance) / (speed)
. = (60 km) / (48 km/h)
. = 1.25 hours .
#3). This one wants you to find SPEED. Use the equation in the form of
. SPEED = (distance) / (time)
but be careful. The time has to be in hours. 55 minutes = 55/60 of an hour.
. SPEED = (distance) / (time)
. = (60 km) / (55/60 hour)
. = (60 x 60 km) / (55 hour)
. = 65.45 km/hr .
#4). This one wants you to find TIME. (It says "How long ?".)
It's two trips, so you have to find the time for each trip.
First trip: TIME = (distance)/(speed) = (24 km)/(65 km/hr) = 0.369 hr
Second trip: TIME = (distance)/(speed) = (50 km)/(80 km/hr) = 0.625 hr
Total time for both trips = (0.369 hr) + (0.625 hr) = 0.994 hour
