A car covers a certain distance at a constant speed of 45km/h in 4 hours. If the car moves at a speed of 40km/h, how much more time (in minutes) will it take to cover the same distance?
- A40
- B25
- C20
- D30
Solution & Step-by-step Explanation
First, let's compute the constant distance covered by the car:
Distance=Speed
1
×Time
1
=45km/h×4 hours=180km
Now, let's find the new time taken to cover this same distance at 40km/h:
Time
2
=
Speed
2
Distance
=
40
180
=4.5 hours=4 hours 30 minutes
The extra time taken is:
Difference=Time
2
−Time
1
=4.5−4=0.5 hours=30 minutes
Distance=Speed
1
×Time
1
=45km/h×4 hours=180km
Now, let's find the new time taken to cover this same distance at 40km/h:
Time
2
=
Speed
2
Distance
=
40
180
=4.5 hours=4 hours 30 minutes
The extra time taken is:
Difference=Time
2
−Time
1
=4.5−4=0.5 hours=30 minutes