Lesson 4.1 · Place Value
Counting to 120
You already know how to count to 100. But counting does not stop there! In this lesson you will count all the way to 120, starting from any number.
Count on from any number
You don't have to start at 1. You can start at any number and keep going.
Start at 46: forty-six, forty-seven, forty-eight, forty-nine, fifty.
After a number that ends in 9, the tens go up by one and the ones start over at 0. So 49 is followed by 50, and 79 is followed by 80.
Past 100
After 100, the numbers sound like "one hundred" plus a number you already know.
101, 102, 103, 104, 105
106, 107, 108, 109, 110
111, 112, 113, 114, 115
116, 117, 118, 119, 120
101 is "one hundred one." 115 is "one hundred fifteen." 120 is "one hundred twenty."
The pattern keeps going
Numbers after 100 follow the same pattern as 1 to 20. Just put "one hundred" in front. After 109 comes 110. After 119 comes 120.
Worked example: Count on
Count on from 97. Say the next four numbers.
Ninety-seven, 98, 99, 100, 101.
After 99 comes 100. Then keep going: 101.
Worked example: The number after
What number comes right after 109?
The ones are 9, so the next number ends in 0. After 109 comes 110.
Worked example: Count back
What number comes just before 111?
Count back by one: 111, 110. The number before 111 is 110.
Common mistake
After 109, don't say "one hundred ten-zero" or write 1010. The number is 110. It has just three digits: 1, 1, 0.
Practice
What number comes right after 59?
Type a number.
What number comes right after 100?
Type a number.
Count on: 101, 102, 103, ___. What number is missing?
Type a number.
What number comes just before 90?
Type a number.
What number comes right after 119?
Type a number.
Count on: 108, 109, 110, 111, ___. What number is missing?
Type a number.
Which shows the number one hundred seven?
Count back: 120, 119, ___. What number is missing?
Type a number.