How do you convert 42 cm to mm? Prealgebra Ratios, Proportions, Units and Rates Unit Conversions 1 Answer MeneerNask Nov 17, 2016 Multiply by #10# Explanation: #1cm=10mm#, so: #42cancel(cm)xx(10mm)/(1cancel(cm))=42xx10mm=420mm# Answer link Related questions How do you convert 73 mi/h = ____km/s? Every morning for breakfast, Mika drinks 20 cL of orange juice. How many milliliters of orange... David takes 300 milligrams of medicine every day. How many grams is this? A manufacturer ships its product in boxes with edges of 4 inches. If 12 boxes are put in a... How many feet is 15 miles? How many feet in a mile? How many meters in a mile? How many feet are in .55 miles? How many miles are in 100 feet? How do you find out how many feet are in a mile? See all questions in Unit Conversions Impact of this question 2494 views around the world You can reuse this answer Creative Commons License