Question

A boy runs one km in12 minutes . How long he will take to run 400 m

Answer 1

1 km = 1000m

∴ 1000m = 12  

400 m = x

by cross multiplying  

1000x = 12 * 400

x = 12 * 400 / 1000

x = 12 * 4 / 10

x = 48 / 10

x = 4.8 mins

pls mark me as brainliest