How many millimeters are there in 5 meters?

The prefix “milli-” means 1,000. There are 1,000 millimeters in 1 meter, so there are 5,000 millimeters in 5 meters. Alternatively, use dimensional analysis to convert: \((5meters) \times \frac{\mathrm{100cm} }{\mathrm{1meter}} \times \frac{\mathrm{10mm} }{\mathrm{1cm}} = 5000 cm\)
1 Kilometer = 1,000 Meters
1 Meter = 100 Centimeters
1 Centimeter = 10 Millimeters