Question

A car covers a distance in 45 minutes moving at 80 km/h. How long will the car take to cover the same distance at 120 km/h?​

Answer 1

The car will take 30 minutes to cover the same distance at 120 km/h.

Step-by-step explanation:

To find out how long it will take the car to cover the same distance at 120 km/h, we can use the formula:

time = distance / speed

Given that the car covered the distance in 45 minutes (0.75 hours) at 80 km/h, we can calculate the distance covered using the formula:

distance = speed × time

distance = 80 km/h × 0.75 h = 60 km

Now we can use the calculated distance and the new speed of 120 km/h to find the time it will take:

time = distance / speed = 60 km / 120 km/h = 0.5 hours = 30 minutes

Answer 2

hi

first thing to figure is the distance.

as distance = time *speed

with :

distance in km

time in = hour

an speed in = km/h

What do we have ? Speed is 80 km/h and is already in the good unit.

time is 45 minutes. But I need speed in hours and not in minutes, so

45 minutes is : 45/60 = 3*15 / 3*20 = 3*3*5 / 3*5*4 = 3/4 of an hour.

so distance is : 3/4 * 80 = 3 *4*20 / 4*1 = 3*20 /1 = 60

Distance is 60

Now if my speed is 120, and I have 60 km to do, as Time =

Distance/Speed we have = 60/120 = 0.5

note : the result is given in unit of time .Here the result say that we need an half unit of time to cover the distance.

As the unit we use is hours ( as speed is km/h ) so the math say : half an hour. Which is 30 minutes.

If speed were 150 km/h , the calculus would have been : 60/150 = 6/15 = 3*2 /5*3 = 2/5 of an hour.

and 2/5 of an hour composed of 60 minutes is :

2/5 * 60 = 2*60 / 5 = 2* 15*4 / 5 = 2*5*3*4 /5 = 24

24 minutes.