1. Number and place value

Lesson

So far, we have seen how to read, write and use place-value blocks to make four-digit numbers.

What number is represented by these blocks?

Worked Solution

Idea summary

We can use a place value table to count the number of blocks.

This video looks at how we can break up numbers with place value, and how we can use that to solve problems.

Enter a three digit number into the applet and drag the place value cards around to see what amount each digit represents.

The place value cards can be used to write the expanded form of the numbers.

Complete the boxes with the missing numbers to write 728 in expanded form.

728=⬚+20+⬚

Worked Solution

Idea summary

We can use a place value table to write a number in expanded form.

This video shows you how to use a number expander to write a number in different ways. Why not try making a number expander with paper?

We have written the number 305 in a number expander.

Complete the boxes below to make the sentences correct.

a

This number is made up of ⬚ hundreds and 5 units.

Worked Solution

b

We can also write the number using only tens and units.

Writing it this way, 305 is made up of ⬚ tens and 5 units.

Worked Solution

Idea summary

Even though we might think of 500 as 5 hundreds, we can also think of it as 50 tens, or 500 units.