A 2-digit number refers to a value between 10 and 99. The number is made up of two digits which represent tens and ones.

Use known facts to find pairs of numbers that total 100

Maths

In this unit pupils will use known facts to find multiples of ten that compose 100  and use known facts to find complements to 100.  In the future unit pupils will find a 2-digit number and a 1 or 2-digit number that compose 100. Pupils will position 3-digit numbers on a number line and estimate the position of 3-digit numbers on unmarked number lines. They will compare and order 3 digit numbers.

In the prior unit pupils reviewed and secured previous knowledge of add 3 addends, understanding they can be added in any order, bridging through 10. In this unit pupils will use known facts to find multiples of ten that compose 100  and use known facts to find complements to 100.

Securing place value to 100 and applying to addition and subtraction

Which of these 2-digit numbers is a multiple of ten?

What is 100 subtract 6? Use the number square.

Two 2-digit numbers total 100. If the first number has 10 ones, the second number is ...

No, because the one digits do not total 10

No, because the tens digits do not total 90

100 is composed of 7 tens and {{ }} tens.

If I know that 2 + 8 = 10 what else do I know?

Izzy was running 100 m. She fell over at 60 m. How many more metres did she have to run?

This lesson will soon be taken down.

Use known facts to find pairs of numbers that total 100

Lesson outcome