How to Multiply Numbers Quickly Using the Distributive Property
Multiply faster!
Jason Marshall, PhD
The distributive property says that if we take the sum of some numbers and multiply it by some other number, the result is the same as if we first individually multiplied each number in the sum and then added these all up. It may not seem like this fact would help you multiply faster, but it does!
For example, if you have to solve the problem 7×212, you can use the fact that 212 = 200+10+2 to turn the problem 7×212 into the problem 7x(200+10+2). Why is that helpful? Because it allows you to turn one big and relatively difficult multiplication problem into three easy ones…and that’s always a good trade-off.
Here’s how it works: Since 7×200=1,400; 7×10=70; and 7×2=14; we see that 7×212=(7×200)+(7x 10)+(7×2)=1,400+70+14 = 1,484.
For more, see How To Multiply Quickly and What Is The Distributive Property?
Multiplication Symbol image courtesy of Shutterstock
About the Author
Jason Marshall is the author of The Math Dude’s Quick and Dirty Guide to Algebra. He provides clear explanations of math terms and principles, and his simple tricks for solving basic algebra problems will have even the most math-phobic person looking forward to working out whatever math problem comes their way.