Finding numbers that are halfway between two lots of numbers
Question: What number is halfway between 63 and 103?
Step One: Find the difference between 63 and 103 by counting on in tens from 63 to 103.
Step Two: Divide the difference by 2 (half)
Step Three: Add this number to the original.
Step One: 63 + 40 = 103
Step Two: 40 divided by 2= 20
Step Three: 63 + 20 = 83
Halfway between 63 and 103= 83
Rounding numbers to the nearest lot of ten
Question: Round 63 to the nearest lot of ten
Step One: What lots of ten are either side of 63?
Step Two: What is halfway between 60 and 70?
Step Three: Is 63 less than, equal to or more than 65?
Step Four: Round to the lower lot of ten.
Step One: 60 and 70 (draw a number line to help if necessary)
Step Two: 65 is halfway between 60 and 70
Step Three: 63 is less than 65.
Step Four: 63 is closer to 60 than 70.
The nearest lot of ten to 63=60
This can all be plotted on a number line to help. See the picture