my week 8 maths bored

hello my name is Ruby this is my maths bored for this week the question was 20 divided by 2=    

Week 8 math's

Hello my names Ruby

 This week i have been rounding and compensating in math's my Goal was to use  rounding and compensating to solve Addison and subtraction problems.i have made a slide withe some examples.Ween you are compensating you have to mace the number closest to the next teen you round it up to that number then pot it all together and then subtract the number  that you added on at the start.