Things You'll Need:
- Japanese Abacus
-
Step 1
Lay the abacus horizontally in front of you with the side containing only one bead at the top, furthest away from you, and the side with four beads at the bottom, closest to you. The top beads stand for multiples of five, and the bottom beads stand for multiples of one.
-
Step 2
Enter a number into the abacus by starting on the right side using each row of beads to stand for one number. For example, to enter 1,254 the furthest row on the right would be the number 4, the row to the left of it would be 5, the row to the left of that would be 2, and the row to the left of that would be 1.
-
Step 3
Enter the numbers by sliding the appropriate number of beads from the bottom up to the bar in the middle. For the number 4, you would slide all 4 beads up. For 2 you would slide 2 beads up, and so on.
-
Step 4
Enter the number five by finding the appropriate row and slide the one single bead at the top down. The single beads that are above the bar in the middle count up starting with 5 on the far right. The next bead would be 10, then 15, and so on.
-
Step 5
Add numbers by sliding more beads up or down. For example, if you want to add the number 3 to 1,254 you would start with the row where you have entered the number 4. Since you do not have 3 single beads left to add, you add one which turns 4 into 5. To show this, you slide the 4 beads back to their original position and slide the single 5 bead down. Then slide 2 beads back up. You have just added 4 + 3 to make 7.
-
Step 6
Move down the rows adding numbers. If a number becomes greater than 10, you move on to the next row. For example, if you add 7 to 1,254 you would start with the 4. Slide the 4 beads back down and slide the 5 bead down. Then push 4 beads back up. This gives you 9 and you have used all your beads, but you have only added 4 + 5. You still need 2 more to make 4 + 7. These 2 get added to the next row to the left. If this row adds up to be more than 9, you add what's left over onto the next row.
-
Step 7
Continue moving across the rows until you have finished adding. To subtract, you follow the same procedure as addition, only moving from left to right instead of right to left.
