The numbers on this number line go up by the same amount each time. Write the missing numbers in the boxes.
We can see that the number line begins with number 20, followed by a missing number, two more missing numbers, and number 40. And we know that the numbers go up by the same amount each time. Number 20 and number 40 end in a zero. They’re both multiples of 10 or numbers from the 10 times table.
Do the numbers go up in 10s each time? 20 add 10 would be 30. 30 add 10 is 40. So that can’t be right. We’ve reached number 40 too soon. So we need a number smaller than 10 to count up by each time.
Let’s try number five. 20, 25, 30, 35, 40. We’ve worked out the rule for the pattern. The numbers go up by five each time. 20, 25, 30, 35, 40. The missing numbers are 25, 30, and 35.