Fill in the gaps in the number line following the sequence. Each next number is 1 greater than the previous one.

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The number line is a series of numbers that follow some rules. The smaller numbers are on the left and the larger on the right. All numbers in the line denote a certain amount. 

Each next number in the line is 1 greater than the previous one. 

This rule applies throughout all numbers. It means we can determine the following number in the series of numbers 1, 2, 3, 4. To find it out, we add 1 to 4: 4+1=5.

Knowing how to find each following number, we can fill in the gaps in the number line if some numbers are missed, as in the example below:

To do this, we need to look at the number that is on the left of the unknown one. This is number 15. We know that the following number is one greater. So, to find it, we add 1 to 15: 15 + 1, that is 16.

Now, let’s find the second unknown number in the line. There is the number 20 on the left of it. Let’s add 1 to 20: 20+1=21. So, the unknown number is 21.

In the line below, the first number is missing.

We know that the following number is 1 greater, so to find the missing one, we need to subtract 1 from 23. Thus, we get the number 22.

Let’s find the other missing numbers in this line. The unknown number that follows 25 is 1 greater, so this is the number 26.  

The last missing number we can find in two ways. We can add 1 to 26 and get 27.

Or we can subtract 1 from 28 and get 27 as well. 

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