WHAT IS ABACUS?
An Abacus is a manual calculating tool that has beads and numbers are placed by moving beads along the rods.
The word “Abacus” is derived from Greek word “ABAX” which means “flat surface.” It consists of rectangular frame with vertical rods and can be made up of different materials such as wood, plastic or metal.
Being an oldest and effective mechanical device for counting we can perform arithmetic operations like addition, subtraction, multiplication and division by using abacus. We can also extract square and cubic roots.
HISTORY OF ABACUS
The History of abacus can be traced as early from 300 BCE starting from the use of “Slabs with lines engraved” in ancient times and stones are placed on sand for calculating. Later these slabs or boards were replaced by Hand Abacus made by stone and metals. With the time people kept on developing the abacus and as a result we have modern abacus. Chinese played an important role in development of modern abacus that was later improved by Japan.
Difference between Suanpan and Soroban Abacus
Chinese Abacus is called Suan-pan, divided into two decks. Upper deck consists of two upper beads and lower deck has five lower beads in each rod making it total of 7 beads in each rod. Whereas, Japanese Abacus is called Soroban, also divided into two decks. Upper deck has one bead and lower deck has four beads in each rod making it total of 5 beads in each rod.
Suan-pan uses base 16 numbering system whereas, Soroban uses base 10 numbering system.
Soroban is widely use to teach mathematics as it uses base 10 numbering standard from 0-9 that we use in our daily life.
BENEFITS OF LEARNING ABACUS
Despite being an oldest tool for math, it is still widely used around the world. Because of its benefits, many schools are compelled to incorporate abacus program. Math, being a subject is liked by very few or majority have math anxiety. Here comes abacus for our rescue and makes math a fun learning. This results in loss of fear for math. Learning abacus also plays vital role in brain development by enhancing concentration, listening skills, memory retention, visualization skills, logical reasoning and speed calculation. After mastering abacus, mental math capability is full fledge developed that a child can calculate complex math problems faster than a calculator.
In Soroban upper bead is called as Heavenly bead and lower beads are called as Earthy Beads. Upper and lower beads are divided by a bar called calculation bar or reckoning bar and the beads that are touching the calculation bar are read in final answer.
The upper bead has a value of 5.
Each lower bead is equals to 1.
Values are placed by moving beads up and down on respective rods. Soroban may have 7 rods, 9 rods, 12 rods or even 17 rods. If the Soroban is half in size then the extreme right rod is Units rod and next left rod to the Units rod is Tens rod then Hundreds rod then Thousands rod and goes on. If the Soroban has 12 or 17 rods then we take center rod as units rod and next left rod to the units rod is tens rod.
Moving Beads on Soroban
Thumb and index (pointer) finger of Right hand are used to move beads up and down along the rod.
Lower beads are always moved Up by Thumb and are moved down by Index finger.
Upper beads are moved Up and Down by Index finger.
Addition by Soroban
Whenever, we are adding numbers we move beads towards the calculation bar. And when subtraction I done beads are moved away from the calculation bars.
To Add 2 and 5 together
First, two is placed on unit’s rod of abacus means two lower beads are moved up to touch the calculation bar.
Now, to add 5
We move upper bead on unit’s rod down to touch the calculation bar.
As a result we get Upper bead and two lower beads touching the calculation bar on unit’s rod which represents the value 7. So the answer would be 7.
Subtraction by Soroban
To Subtract 6 from 9
First, we will place 9 on abacus means all the beads on units rod will touch the calculation bar.
Now to subtract 6,
We will move upper bead up and one lower bead down.
As a result, we get three lower beads touching the calculation bar and this represents the value 3. So the answer would be three.