Question

Emily ran 500 metres in 100seconds. Find the speed in km per hour

Answer 1

18 KM/H.

Explanation:

S= D / T or 500 meters / 100 seconds. The answer is 5M/S. To calculate the speed per hour, multiply the distance by 3600 (60 seconds times 60 minutes equals one hour). 5 x 36oo = 18 KM/H.

Answer 2

speed = 18 km / hour

Explanation:

To solve the question, we will use the formula;

speed = distance / time

since we are ask to find the distance in km per hour, then distance given to us is in meter, we will have to change it to kilometer and the time given to us is in second, we will also have to change to hour before we insert the values into our formula.

we are to change 500 m to km

1 km = 1000 m

x = 500m

1000x =500

Divide both-side of the equation by 1000

x = 500/1000

x=
`(1)/(2)` km

Distance =
`(1)/(2)` km

We will then change 100 seconds to hour

1 hour = 3600 s

x = 100 s

3600 x = 100

Divide both-side of the equation by 3600

x = 100 / 3600

x =
`(1)/(36)` hour

Time =
`(1)/(36)` hour

We can now proceed to substitute our values into the formula;

speed = distance / time

speed =
`(1)/(2)` km /
`(1)/(36)` hour

speed =
`(1)/(2)` km ×
`(36)/(1)` hour

speed =
`(36)/(2)`

speed = 18 km / hour