Question

Show that at 40km/h it takes 1 minute and 30 seconds to travel 1km

Answer 1

Let's compare apples to apples and oranges to oranges. This means converting seconds to hours or hours to seconds: 3600 sec = 1 hour.

40 km/h = 40 km/h times (1 hour) / (3600 sec) = (1/90) km/sec

Then the time req'd to travel 1 km is:

distance 1 km
----------- = time, or ---------------- = 90 sec = 1 1/2 minutes
rate 1 km
----------
90 sec

Answer 2

40 km / hr is the speed
to change hr to sec you'll multiply by 60 × 60
40 /60 × 60
= 4 / 6×60
= 2/3 ×60
= 1/ 3×30
= 1/90
1 minute = 60 seconds
Therefore, 90 sec = 1 minute and 30 seconds