A boy runs at a speed of 20 m/s.How much time will he take to cover a distance of 1 km?

2 Answers
Nov 15, 2016

Answer:

I got #50s#

Explanation:

1 km corresponds to #1000m# so considering that:
#"speed"="distance"/"time"#
we can rearrange and get:
#"time"="distance"/"speed"=1000/20=50s#

Dec 3, 2016

Answer:

It will take 50 seconds to run 1000 metres

Explanation:

Using ratio in the fraction style format

Given:#" "("distance")/("time")-> ("metres")/("seconds")->20/1#

We need 1 km which is the same as 1000m

Let the unknown time in seconds be #t#

#20/1-=1000/t#
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

To change 20 into 1000 multiply by 50

If you multiply by 1 you do not change the value. However, 1 can come in many forms.

#color(green)(20/1color(magenta)(xx1)" "-=" "20/1color(magenta)(xx50/50))color(blue)(" " =" " 1000/50)#

It will take 50 seconds to run 1000 metres