Number (mult/div)

Lesson

When we need to divide a three digit number, such as $400$400 by a one digit number, such as $8$8, we can use arrays and area models to help us.

We can also start with a simpler problem, such as $40$40 divided by $8$8, (also written as $40\div8$40÷8) which helps us as well.

Let's use an area model to find the answer to $133\div7$133÷7.

We set up the area model using a rectangle like this.

$7$7 Total area: $133$133 Now if we don't know straight away what $133\div7$133÷7 is, we start with something we do know, like groups of $10$10.

Fill in the area used so far if we take out $10$10 groups of $7$7.

$10$10 $7$7 $\editable{}$ Total area: $133$133 How much area is remaining?

$10$10 $7$7 $70$70 $\editable{}$ Total area: $133$133 What is the width of the second rectangle?

$10$10 $\editable{}$ $7$7 $70$70 $63$63 Total area: $133$133 Using the area model above, what is $133\div7$133÷7?

We want to find $108\div6$108÷6.

Fill in the boxes to complete the area model.

$10$10 $\editable{}$ $6$6 $\editable{}$ $\editable{}$ Total area: $108$108 Using the area model above, what is $108\div6$108÷6?

We want to find $138\div6$138÷6.

Fill in the widths of the rectangles on the area model.

$\editable{}$ $\editable{}$ $6$6 $66$66 $72$72 Total area: $138$138 Using the area model above, what is $138\div6$138÷6?

Divide three-digit whole numbers by one-digit whole numbers, using concrete materials, estimation, student-generated algorithms, and standard algorithms