Subtracting two numbers directly is the opposite of adding two numbers directly. When subtracting the user clears, or removes, beads from the horizontal bar.
In the problem 9-3=6 the user sets 9 in the ones column.
She then asks, "Can I clear 3 directly?" Since she can, she moves the three 1-beads away from the horizontal bar.
The abacus then reads 6 as shown in the picture below.
Review the PowerPoint "Subtracting Directly" for practice on this type of computation.