Multiplication and Division
Long Division
Solving Long Division Problems
To solve long division problems, you'll use three math skills you've already learned: division, multiplication, and subtraction. It's a good idea to make sure you feel comfortable with all three skills. If you think you might need more practice, take some time to review those lessons first.
When solving a long division problem, the number under the division bracket is split into smaller numbers. This makes division easier. Plus, you can use a familiar tool, like a times table, to help.
Let's see how solving a long division problem works.
Remember the manager of the used car dealership who wanted to divide 42 cars among 3 rows? Let's find out how many cars he should put in each row.
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We'll use long division to solve this problem: 42 / 3.
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Long division follows a pattern. You follow the same basic steps again and again until the problem is complete. If this seems confusing, don't worry. We'll go through it step by step.
We'll begin with the left digit under the division bracket. That means we'll start with the 4...
We'll begin with the left digit under the division bracket. That means we'll start with the 4... and we'll figure out how many times it can be divided by 3.
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Now it's time to solve 4 / 3.
We can use the times table. We'll look at the 3's column.
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Since 4 is the number we're dividing, we need to locate the number that is the closest to 4. The number can't be any larger than 4.
3 is the closest to 4.
Next, we'll find the row 3 is located in. It's the 1's row.
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That means 3 goes into 4 one time.
We'll write 1 above the 4 and the division bracket.
The next step is to multiply the 1 and 3.
Whenever you multiply a number by 1, that number stays the same. So 1 x 3 is 3.
We'll write 3 below the 4.
The next step is to subtract.
Now we solve 4 - 3.
4 - 3 is 1. We'll write 1 below the 4 and 3.
Since our answer is 1, we're not done yet. We'll know our problem is complete when the answer to our subtraction problem is zero. Plus, there's still another digit under the bracket: 2.
We'll bring the 2 down and rewrite it next to the 1.
See how the 1 and 2 look like the number 12? That's the next number we need to divide.
12 is large enough to be divided, so we'll figure out how many times it can be divided by 3.
Let's look at the 3's column. Since 12 is the number we're dividing, we'll find the number closest to 12. Remember, the number can't be any larger than 12.
The 3's column has a 12. It would be impossible to get closer than that!
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Now we find the row 12 is located in.
It's the 4's row. 3 goes into 12 four times.
We'll write 4 above the 2 and the division bracket.
Now it's time to multiply the 4 and 3.
4 x 3 is 12.
Write the 12 beneath the 12.
We'll set up our subtraction problem.
Now it's time to solve 12 - 12.
12 - 12 is 0. Write 0 beneath the line directly below the 2 and 2.
The answer to our subtraction problem is 0. That means we're done! 42 / 3 = 14.
Now click these and try it. Solve these long division problems.
