Think of a number line as being like a tape measure, except you don’t have to be careful about getting the distances right. Just draw a line and pick a spot for 0. Given the numbers and operations you’re dealing with, I’d suggest using the far left-hand end for 0. Then pick a value for the right hand end – again, given the numbers you’re using, I’d suggest 100. Then halfway along the line would be 50, and you can put in 10, 20, 30, and so on just by eyeing it. They seem, then, to want you to put in the units: 1, 2, 3, and so on. Again, you just put them roughly where they should go.

To do the problems, then, you’re going to find the first number on your number line and move the proper distance in the proper direction for the second number. Assuming 0 is on the left and 100 on the right, you’ll always move to the right (bigger numbers) for addition and left for subtraction. Happily, all you have here is addition.

So – for your first problem, you’ll put a dot at 45, then move 18 to the right to see what the sum is. For the second, put a dot at 27 and move 65 to the right. And so on.

Hope that helps.

ok well i’m just guessing you add all the numbers up like 45+18…. and so on and then draw a straight line then put the largest number at the right or the end and then put the smallest number at the left or the start then fill up the number line with the second smallest at the left and then go up until the second largest number is before the last number

i hope that is right and helps

here is a site about the subject

http://www.allenandunwin.com/teachingmaths/secure/empty.htm

hope it helps

just put a question mark beside it and write a note to his teacher shell/hell understand.