what are small friends and big friends in abacus ?

In the context of using an abacus, a “small friend” typically refers to a bead located in the bottom section of each rod or wire. Abacus beads are commonly divided into two groups: the “small friends” and the “big friends.”

The “small friends” are the beads positioned below the horizontal beam, and they represent units (ones) in the decimal number system. The “big friends” are the beads positioned above the horizontal beam, and they represent groups of tens.

When performing calculations on an abacus, moving the beads representing small friends allows for counting individual units, while moving the beads representing big friends enables counting groups of tens. This arrangement facilitates arithmetic operations such as addition, subtraction, multiplication, and division.

let’s use a simple example to explain the concept of “small friend” on an abacus.

Consider the number 573. On an abacus, this would be represented using the small and big friends. Each rod on the abacus represents a place value in the decimal system: units, tens, hundreds, and so on.

Here’s how you would represent 573 on an abacus:

1. Units (small friends): On the units rod, you would have 3 small beads (small friends) representing 3 units.
2. Tens (big friends): On the tens rod, you would have 7 big beads (big friends) representing 7 tens.
3. Hundreds (big friends): On the hundreds rod, you would have 5 big beads (big friends) representing 5 hundreds.

So, visually, on an abacus, you would see something like this:

In this representation, the small beads (small friends) at the bottom represent the units place, the big beads (big friends) above represent the tens place, and so on. This allows for performing arithmetic operations by moving the beads accordingly.