Two Ways of Sharing in Division—Let's Practise!

Two Ways of Sharing in Division—Let's Practise! exercise

• Can you find another way of sharing these groups?

  Hints

  Use the arrays to help you.

  • The rows represent the groups.
  • The columns show how many are in each group.

  Here we can see one column circled.

  Remember, we use the same numbers both times.

  For example, if 18 can be divided into 2 groups of 9, it can also be divided into 9 groups of 2.

  Solution

  15

  • 3 groups of 5
  • 5 groups of 3

  21

  • 7 groups of 3
  • 3 groups of 7

• How can we share these numbers?

  Hints

  How many rows are there in the array? This represents the number of groups.

  How many spots in each row? This represents the number in a group.

  For example, here 8 has been divided into 4 groups of 2. It could also be divided into 2 groups of 4.

  Solution

  Here we can see two ways of sharing 6:

  • 2 groups of 3
  • 3 groups of 2

  ______________________________________________________

  10

  • 2 groups of 5
  • 5 groups of 2

  20

  • 5 groups of 4
  • 4 groups of 5

  24

  • 6 groups of 4
  • 4 groups of 6

• What are the two ways these numbers have been shared?

  Hints

  How can the numbers 16 and 18 be shared? What are the factors of 16 and 18? Are there factors that match the arrays?

  Look at the number of rows. This represents the number of groups. This pictures shows there are two rows altogether.

  How many spots in a row? This represents the number in a group. This pictures shows eight spots in one row.

  Solution

  16

  • 2 groups of 8
  • 8 groups of 2

  18

  • 3 groups of 6
  • 6 groups of 3

• What is the number?

  Hints

  Look at the number of rows and columns. Can you think of a number that has these factors?

  Multiply the number of rows by the number of columns.

  For example, these arrays show:

  • 2 groups of 5
  • 5 groups of 2

  We can multiply 2 x 5 to get 10. These arrays show two ways of sharing 10.

  Count all of the dots in an array to check.

  Solution

  These two arrays showed two ways of sharing 8.

  • 2 groups of 4 = 8
  • 4 groups of 2 = 8

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  Two ways of sharing 27

  • 3 groups of 9
  • 9 groups of 3

  Two ways of sharing 18

  • 2 groups of 9
  • 9 groups of 2

  Two ways of sharing 12

  • 2 groups of 6
  • 6 groups of 2

• What are two ways of sharing 12?

  Hints

  How many rows of dots are there? This shows the number of groups.

  How many dots in a row? This represents the number in a group.

  For example, this array shows 2 groups of 4.

  Solution

  Two ways that 12 can be shared are:

  • 4 groups of 3
  • 3 groups of 4

• Can you find all of the ways of sharing these numbers?

  Hints

  List all of the factors of each number. Which ones can we multiply together to make the number?

  Draw some arrays to help you.

  For example, this array has 10 groups of 3. It will help you fill in some answers above.

  Solution

  24

  • 1 group of 24
  • 2 groups of 12
  • 3 groups of 8
  • 4 groups of 6
  • 6 groups of 4
  • 8 groups of 3
  • 12 groups of 2
  • 24 groups of 1

  30

  • 1 group of 30
  • 2 groups of 15
  • 3 groups of 10
  • 5 groups of 6
  • 6 groups of 5
  • 10 groups of 3
  • 15 groups of 2
  • 30 groups of 1