A car takes 20 mins to cover a distance of 15 km.Calculate its speed in km/h?
回答 (10)
2016-07-03 9:58 am
Distance
= 15 km
Time taken
= 20 min
= (20/60) h
= 1/3 h
Speed
= Distance ÷ (Time taken)
= 15 ÷ (1/3) km/h
= 15 × 3 km/h
= 45 km/h
= 15 km
Time taken
= 20 min
= (20/60) h
= 1/3 h
Speed
= Distance ÷ (Time taken)
= 15 ÷ (1/3) km/h
= 15 × 3 km/h
= 45 km/h
2016-07-03 11:25 am
V = s / t
V = 15 km / 20 minutes = 0.75 km / minute
but 20 minutes is 20/60 = 1/3 of one hour
so V = 15 / ( 1/3) = 15 * 3 = 45 km/hr
By converting the time prior to calculation the result becomes quite trivial.
and by converting both s = 15000 m t = 20 * 60 = 1200 s
so V = 15000 / 1200 = 12.5 m/s
V = 15 km / 20 minutes = 0.75 km / minute
but 20 minutes is 20/60 = 1/3 of one hour
so V = 15 / ( 1/3) = 15 * 3 = 45 km/hr
By converting the time prior to calculation the result becomes quite trivial.
and by converting both s = 15000 m t = 20 * 60 = 1200 s
so V = 15000 / 1200 = 12.5 m/s
2016-07-03 10:41 am
perhaps an easy way to is to compute the speed in 'm/s', then convert it to the desired unit.
20 min = 20 x 60 seconds
15km = 15 x 1000 = 15000 metres
=> speed = distance / time = 15000 / [20 x 60] = 12.5 m/s
to convert from 'm/s' to km/h, multiply with (18/5)
=> km/h = 12.5 x 18/5 = 45 km/h
[also to convert from 'km/h' to 'm/s', multiply with (5/18). like 54 km/h = 54 x (5/18) = 15 m/s]
hope this helps
20 min = 20 x 60 seconds
15km = 15 x 1000 = 15000 metres
=> speed = distance / time = 15000 / [20 x 60] = 12.5 m/s
to convert from 'm/s' to km/h, multiply with (18/5)
=> km/h = 12.5 x 18/5 = 45 km/h
[also to convert from 'km/h' to 'm/s', multiply with (5/18). like 54 km/h = 54 x (5/18) = 15 m/s]
hope this helps
2016-07-03 10:11 am
15 km in 20 minutes is
30 km in 40 minutes and
45 km in 60 minutes.
Answer: 45 km/h
30 km in 40 minutes and
45 km in 60 minutes.
Answer: 45 km/h
2016-07-03 10:37 am
No one can calculate it's instantaneous speed/s unless the question additionally stated that the car moved at constant speed. None the less, the average speed of the car for this time & distance is as given by those (above). :>)
2016-07-03 10:06 am
45km/h
2016-07-03 9:52 am
45km/hr....
its very easy...need more help...jst comment below my answer
its very easy...need more help...jst comment below my answer
2016-07-03 9:50 am
20 x 3 = 60
15 x 3 = 45
45km/hr
15 x 3 = 45
45km/hr
2016-07-03 9:45 am
45KM
(20 minutes
60 minutes=1 hour
20 minutes=15km
Multiply 15km by 3 to become 1 hour of driving)
(20 minutes
60 minutes=1 hour
20 minutes=15km
Multiply 15km by 3 to become 1 hour of driving)
2016-07-03 9:43 am
45 km/h
收錄日期: 2021-04-18 15:18:11
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