7 Math Tricks to Help You in Everyday Situations
Some people have a few tricks up their sleeve to make everyday life easier, like how to quickly multiply 2-digit numbers. We at 5-Minute Crafts would like to show you how some of our favorite math tricks work.
1. Multiply a 2-digit number by 11.
Add the 2 numbers, then add the result in between.
Note: There are also cases where you need to carry the 1, as in 57×11 = 627. The process behind it is 5 + 7 = 12, and the 1 will be added to the 5.
2. Get 20% from a number.
Multiply the number by 20, and simply divide the result by 100.
3. Multiplication made easy
If you do multiplication by tens, it becomes a bit easier. Break up your number in tens, plus the remaining number, then follow the distributive property shown above.
4. Divide by 10, 100, and 1000
When dividing a number by 10, move the decimal one point to the left. If dividing by 100, move it 2 spots to the left; and by 1,000, 3 spots to the left.
5. Multiply a 2-digit number by 5.
For even numbers, divide them by 2 and then multiply them by 10, or simply add a 0 at the end. As for odd numbers, they’ll have 1 remainder when you do this. Add it at the end, and it’ll become a 5.
6. Multiplying by 9
First, you’ll need to subtract 1 from the number you want to multiply. Then subtract the result from the number 9. Finally, the result will be the junction of these 2 numbers.
7. Add 2-digit numbers quickly.
Simply split the numbers into tens and ones. Then add them on their own (tens with tens, ones with ones). To finish up, simply add both results.