Divisibility Tips and Tricks

Math-Divisibility Tips and Tricks

Word Problem of The Day

CCA is preparing juice boxes for a field trip. Each pack contains 6 juice boxes, and CCA buys 14 packs. The teacher wants to divide all the juice boxes equally among 7 groups of students. How many juice boxes will each group get?

When is divisibility useful

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In math class (of course)Dividing something into equal

groupsCalculating moneyAnd more

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Factors are numbers that you can multiply together to get an answer.

For example:

Factors of 18 ....

First...

1, 18

2, 93, 6

What is a

factor?

All the factors of 18 are

1, 2, 3, 6, 9,18

You can divide 18 by any of these numbers and get a whole number (not a decimal or fraction).

How do you know to check if a number is a factor?​

Some numbers you just have to divide and try out.​ ​

Tips and Tricks...

But others there are some....​ Tips and Tricks!!!!!

A number is divisible by 2 if it is an even number.​   Example: 586 is divisible by 2 because 6 is even.​ ​ A number is divisible by 3 if the digits add to a number also divisible by 3.​   Example: 312 : 3 + 1 + 2 = 6 ​   Since 6 is divisible by 3, then 312 is also.​ ​ A number is divisible by 4 if the last 2 digits are divisible by 4.​   Example: 704 The last two digits (04) is divisble by 4.​ ​ A number is divisible by 5 if it ends in 0 or 5.​   Examples: 65, 905, 810, 675​ ​ A number is divisible by 9 if the digits add to a number also divisible by 9.​   Example: 936 : 9 + 3 + 6 = 18 ​   Since 18 is divisible by 9, then 936 is also.​ ​ A number is divisible by 10 if it ends in 0.​   Examples, 90, 200, 640, 980

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