Science, Tech, Math › Science How to Cancel Units - Chemistry Metric Conversions Share Flipboard Email Print Science Chemistry Basics Chemical Laws Molecules Periodic Table Projects & Experiments Scientific Method Biochemistry Physical Chemistry Medical Chemistry Chemistry In Everyday Life Famous Chemists Activities for Kids Abbreviations & Acronyms Biology Physics Geology Astronomy Weather & Climate By Todd Helmenstine Todd Helmenstine is a science writer and illustrator who has taught physics and math at the college level. He holds bachelor's degrees in both physics and mathematics. our editorial process Todd Helmenstine Updated September 04, 2018 Unit cancellation is one of the easiest ways to keep control of your units in any science problem. This example converts grams to kilograms. It doesn't matter what the units are, the process is the same. Metric to Metric Conversions - Grams to Kilograms It is not difficult to convert units if you use the cancelling method. Todd Helmenstine How Many Kilograms Are in 1,532 Grams? The graphic shows seven steps to convert grams to kilograms.Step A shows the relationship between kilograms and grams. In Step B, both sides of the equation are divided by 1000 g. Step C shows how the value of 1 kg/1000 g is the equal to the number 1. This step is important in the unit cancellation method. When you multiply a number or variable by 1, the value is unchanged. Step D restates the example problem. In Step E, multiply both sides of the equation by 1 and substitute the left side's 1 with the value in step C. Step F is the unit cancellation step. The gram unit from the top (or numerator) of the fraction is canceled from the bottom (or denominator) leaving only the kilogram unit. Dividing 1536 by 1000 yields the final answer in step G. The final answer is: There are 1.536 kg in 1536 grams. Tips for Success Be sure to watch for exact numbers and significant figures. Rounding errors or other inaccuracies can make the difference between a right or wrong answer! Finally, check your conversion to make sure it makes sense. You know a gram is a smaller unit than a kilogram, so if you do the conversion between them the wrong way, you'll wind up with a ludicrous value.