Addition & subtraction - 3rd grade

In this 2nd part, I show how to regroup twice when there are zero tens, using the standard subtraction algorithm. The first part explains the process using a visual model and with numbers that are "written with their parts" (in expanded form): See more 3rd grade math videos: Math Mammoth Grade 3 Curriculum Practice 3-digit subtractions online:

In this 2nd part, I show how to regroup twice when there are zero tens, using the standard subtraction algorithm. The first part explains the process using a visual model and with numbers that are "written with their parts" (in expanded form): See more 3rd grade math videos: Math Mammoth Grade 3 Curriculum Practice 3-digit subtractions online:

I show how to regroup twice in subtraction when there are zero tens. The numbers are written in expanded form (for example 400 + 50 + 2) to make the algorithm as clear as possible. I also compare how it works with base ten blocks (visual model). We have to first break down a hundred into 10 tens, and then break down one of those tens into 10 ones. Then we can subtract. See more 3rd grade math videos: Math Mammoth Grade 3 Curriculum Practice 3-digit subtractions online:

I show how to regroup twice in subtraction when there are zero tens. The numbers are written in expanded form (for example 400 + 50 + 2) to make the algorithm as clear as possible. I also compare how it works with base ten blocks (visual model). We have to first break down a hundred into 10 tens, and then break down one of those tens into 10 ones. Then we can subtract. See more 3rd grade math videos: Math Mammoth Grade 3 Curriculum Practice 3-digit subtractions online:

I show how to read a mileage chart to find distances between places. Then we solve a few word problems related to the chart. Find more 3rd grade math videos at my site:

I show how to read a mileage chart to find distances between places. Then we solve a few word problems related to the chart. Find more 3rd grade math videos at my site:

In this lesson, we learn about parenthesis and how they affect the order in which we do additions and subtractions. Normally, if there are several additions and subtractions, you do them from left to right. But with parenthesis you can change that. In these examples, I draw a bubble or a "balloon" around the operation to be done first - makes math easier and colourful!

In this lesson, we learn about parenthesis and how they affect the order in which we do additions and subtractions. Normally, if there are several additions and subtractions, you do them from left to right. But with parenthesis you can change that. In these examples, I draw a bubble or a "balloon" around the operation to be done first - makes math easier and colourful!

In this lesson I solve a few word problems involving three-digit numbers (addition & subtraction). We also look at a subtraction puzzle with missing numbers. :) The first part of the lesson is here:

In this lesson I solve a few word problems involving three-digit numbers (addition & subtraction). We also look at a subtraction puzzle with missing numbers. :) The first part of the lesson is here: