Divisibility Rules

Skip Counting 1)Skip count by 3 from 3. 2)Skip count by 5 from 65. 3)Skip count by 10 from )Skip count by 6 from 138.

Double and Halve 1)8 x 45 2)4 x 150 3)1.5 x 12

Repeated Doubling 1)Double 2. Double the next number. Repeat. 2)Double 3. Double the next number. Repeat.

1)Find a number with 5 factors. 2)Draw a factor tree for each of the following: a) 10b) 17c) 27

Divisibility A number is divisible by another number if the answer is a whole number. dividend ÷ divisor = quotient A number is divisible if the quotient is a whole number.

Which of the following are divisible by 2? By 5? By 10?

A number is divisible by: 2 if the number is even (ends in 0, 2, 4, 6, or 8) 3 4 5if the ones digit is 0 or if the ones digit is 0

Multiples of 3 Write the first 10 multiples of 3. 3, 6, 9, 12, 15, 18, 21, 24, 27, 30 Notice anything?

1)Shade all of the multiples of 3 in yellow. 2)Choose a two-digit multiple of 3. Add the digits. Is the result divisible by 3? 3)Repeat with another two-digit multiple of three. 4)Write a divisibility rule for 3.

1) Shade all of the multiples of 2 in blue. 2) Which numbers are multiples of both 2 and 3? 3) Can you describe the pattern of the green squares? 4) What other number (not 1) can these numbers be divided by? 5) Write a divisibility rule for 6.

Multiples of 9 Write the first 10 multiples of 9. 9, 18, 27, 36, 45, 54, 63, 72, 81, 90 Notice anything?

A number is divisible by: 2 if the number is even (ends in 0, 2, 4, 6, or 8) 3if the sum of the digits is divisible by 3 4 5if the ones digit is 0 or 5 6if it is divisible by 2 and 3 8 9if the sum of the digits is divisible by 9 10if the ones digit is 0

Which of the following numbers are divisible by 3?

Which of the following numbers are divisible by 6?

Which of the following numbers are divisible by 9?

Use a hundreds chart 1)Circle all the numbers that are divisible by 2. 2)Use a different colour. Circle all the numbers that are divisible by 4. 3)What do you notice?

4) Use a different colour. Circle all the numbers that are divisible by 8. 5) What patterns do you see?

If a number is divisible by 8, what else can we say about it? If a number is divisible by 4, what else can we say about it?

A number is divisible by 4 if the number formed by the digits in the tens and ones place is divisible by 4. We can also say that numbers that can be divided by 4 can be divided by 2 twice. Examples: 44, 72, 88

A number is divisible by 8 if the number formed by the digits in the hundreds, tens, and ones place is divisible by 8. In other words, a number is divisible by 8 if it is divisible by 2 three times. Examples: 520, 272,7896

A number is divisible by: 2 if the number is even (ends in 0, 2, 4, 6, or 8) 3if the sum of the digits is divisible by 3 4if the last two digits are divisible by 4 5if the ones digit is 0 or 5 6if it is divisible by 2 and 3 8if the last three digits are divisible by 8 9if the sum of the digits is divisible by 9 10if the ones digit is 0

Which of the following numbers are divisible by 4?

Which of the following numbers are divisible by 8?