In the previous article, we looked at doing addition on the abacus (do have a read before proceeding onto this article, if you have not done so). Today we are going to have a look at learning how to subtract using the abacus.
Before we start adding or subtracting numbers, always set the abacus to zero. To set your abacus to zero, push all the beads away from the beam.
Just like when counting using the abacus, we need to take note of the unit values. The center of the abacus represents the units, wherein the center column represents a unit.
From the center column, when you move to your left, the units will move to tens, hundreds, thousands, and so on. And as you move to your right, the decimals will move to tenths, hundredths, thousandths, and so on.
Let’s now learn how to subtract with the help of these few examples:
Subtracting a one-digit number
To subtract one-digit numbers, we will use the center column.
Example: 4 – 2 =
In ones column, use your right thumb to push four lower beads up towards the beam.
In ones column, reduce two lower beads by using your right index finger to push them away from the beam.
Count the value represented by the beads. The answer is 2.
Let’s try subtracting bigger numbers!
Question: 43 – 31 =
43 minus 31 uses tens and ones units. So in this example, we need to use the tens and ones units on the abacus.
First, let’s get the value of 43.
In the tens column, use your left thumb to push four lower beads up towards the beam.
At the same time, in the ones column, use your right thumb to push three lower beads up towards the beam.
Now to subtract 31 from 43
In the tens column, reduce three beads by using your left index finger to push them away from the beam.
Simultaneously, in the ones column, reduce one bead by using your right index finger to push it away from the beam.
Count the value represented by the beads. The answer is 12.
How we help!
Solving these examples illustrates that using the abacus is the most efficient and accurate tool to perform subtraction, it does not only help your children to solve these math problems, but it can also help your child to master solving arithmetic mentally.
Mentalmatics has the best teachers to help your child to be proficient in using the abacus. Learning abacus does not only teach your child how to do basic math, but also it develops numerous skills that can be the key of your child’s success in the future.
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