Answer:
A) 80 minutes
Step-by-step explanation:
Since both speeds were traveled at for the same time, adding the time spent travelling at each of the speeds is the total time.
let a be the time travelled at one speed
2a = t
To find the time traveled at each speed, write a formula including the distance. The total distance is the sum of the time travelled at each speed.
d = 100km
d = (50km/h)a + (100km/h)a
d = (150km/h)a Simplified by adding
100km = (150km/h)a Substitute the total distance for "d"
a = 100km ÷ 150km/h Isolating "a" to find
a = 2/3h Time travelled at one speed in hours
Substitute a=2/3h into the total time formula
2a = t
2(2/3)h = t
4/3h = t Total time of trip in hours
t = 4/3h Variable on left side for standard formatting
The speeds are 50km/h and 100km/h. Remember the unit for the answer is in hours.
Convert the answer to minutes. There are 60 minutes each hour.
(4/3)h X 60min/h = (240/3)min
= 80min
Therefore the total time of his trip is 80 minutes.