Question

A train travels 60km in M minutes. If it's average speed is 400km per hour find the value of M?

Answer 1

the value of M is 9 min.

Explanation:

D = RT

The distance D = 60 km
the rate R = 400km/hr
M = the time in mins.

Substitute the values into the D =RT equation and solve.

Change the Rate to 400 km/60 min

`60 km = (400km)/60 min xx M`

Multiply both sides by the inverse of the Rate

`60 xx 60 min/400km = ( 400km)/60 min xx 60 min/(400km) xx M`

This gives

`( 3600 min xx km )/(400 km) = M`

Dividing gives

`9 min = M`

Answer 2

`"speed"=("distance")/("time")`

`"time"=("distance")/("speed")`

`"time"=(60)/400=3/20`

`1/20` of an hour is 3 minutes so `3/20` is 9 minutes