Divisibility Rules
Prime and Composite
Factors
HCF
Prime Factorization
LCM
100
This number divides evenly into all even numbers.
What is 2.
100

A number that has exactly two factors; one and itself.

What is a prime number.

100

What are numbers multiplied together to create a product.

factors.

100

What is the HCF of 36 and 48?

12

100

22x3x5 is the prime factorisation of what number?

60

100

Find the LCM for 7 and 9.

63

200
This number divides evenly into all numbers that end with 5 and 0.
What is 5.
200

This number is the only even prime number.

What is 2.

200

List the factors of the number 24.

What is 8. (1, 2, 3, 4, 6, 8, 12, 24)

200

The HCF between 30 and 25.

What is 5.

200
The prime factorization of 20.
What is 2x2x5?
200

Find the LCM for 12 and 15

60

300
You do this to a number to decide if the number is divisible by the number 3.
What is find the sum of the digits.
300

These are the first 5 prime numbers.

What are 2, 3, 5, 7, 11.

300

List the factors of the number 25.

What is 3. (1, 5, 25)

300

Paul has 16 fish pictures and 12 deer pictures to display. He wants to arrange the pictures in rows with the same numbers of fish and of deer pictures in each row. What is the largest row Paul can make? (Hint: Find the HCF.)

4 rows

300

The prime factorisation of 100.

22x52

300

You buy a lily and an African violet on the same day. You are instructed to water the lily every fourth day and water the violet every seventh day after taking them home. What is the first day on which you will water both plants on the same day? (Find the LCM)

28th Days

400
These are the two numbers that both need to evenly divide into a number to make the number also divisible by 6.
What are 2 and 3.
400

These numbers are the only whole numbers that are neither prime, nor composite.

What is 1 and 0.

400

List the factors for the number 13.

What is 2. (1, 13)

400

The middle school band has 56 members. The high school band has 96 members. The bands are going to march one after the other in a parade. The director wants to arrange the bands into the same number of columns. What is the greatest number of columns in which the two bands can be arranged if each column has the same number of marchers?

8 columns

400

The prime factorization of 25.

What is 52?

400

Molly does ten sit-ups every 3 hours and fifteen push-ups every 2 hours. She does 10 sit-ups and 15 push-ups at 8am.  At what time will she do both? (Find the LCM of 3 and 2.  Then add it to the time.)

every 6 hours she will do both, so 2 PM

500

These numbers all divide equally into 30.

What are 1, 2, 3, 6, 9

500

Is the number 33 prime or composite?

What is composite.

500

List the factors of 30.

What is 8. (1, 2, 3, 5, 6, 10, 15, 30)

500

Megan has 30 brownies and 42 cupcakes to package. She wants to put the same numbers of brownies and of cupcakes in each box. What is the greatest number of boxes she can make? How many cupcakes and how many brownies will each box contain?

6 boxes

 each box will have 5 brownies and 7 cupcakes.

500

32x11 is the prime factorisation of what number?

What is the prime factorization of 99?

500

Hotdogs are sold in packages of 6. Buns are sold in packages of 8.  What is the least number of hotdogs and buns that should be bought to have an equal amount of each? 

24 hotdogs and buns

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