With the abacus a user can add, subtract, multiply, divide, and compute problems with fractions and/or decimals. When teaching a child to compute with the abacus most teachers begin with direct addition. The term direct means the user can push the needed beads to the horizontal bar. Another term that is used is "no synthesis." This means no exchange of beads is needed. The indirect method or synthesis involves exchanging beads.
The problem 3 + 5 = 8 illustrates direct addition. This is also called addition with no synthesis.
The user begins by setting 3: moving three 1-beads to the horizontal bar.
Next the user sets a 5-bead by moving the bead to the horizontal bar. The abacus now reads 8.
Review the PowerPoint Show "Adding Direct" in the list of links below.