Question

how many metres are there in four and a half kilometres

Answer 1

1km =1000m
so 4km=4 x 1000=4000m
halk km=1000/2=500
so 4000+500=4500m

Answer 2

1 km=1000 m
4.5 km= 1000 x 4.5
4.5 km= 4500 m.

Hence there are 4500 metres in four and a half kilometres.