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Adding Two Numbers Directly. .Another term for directly is “no synthesis.” When adding directly all the beads you need are available to push to the separation bar.
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Adding Two Numbers Directly .Another term for directly is “no synthesis.” When adding directly all the beads you need are available to push to the separation bar. From http://www.uabacus.arizona.edu/ Developed by Dr. L. Penny Rosenblum
Set three 1-beads in the units column.Ask: “Can I add 1 directly?”Answer” “Yes I can.”Set a 1-bead in the units column.You now have 4 beads in the unit column.Sum = 4 3+1 = 4 From http://www.uabacus.arizona.edu/ Developed by Dr. L. Penny Rosenblum
5+3 = 8 • Set a 5-bead in the units column.Ask: “Can I add 3 directly?”Answer” “Yes I can.”Set three 1-beads in the units column.You now have 8 beads in the units column.Sum = 8 From http://www.uabacus.arizona.edu/ Developed by Dr. L. Penny Rosenblum
2+2 = 4 • Set two 1-beads in the units column.Ask: “Can I add 2 directly?”Answer” “Yes I can.”Set two 1-beads in the units column.You now have 4 beads in the units column.Sum = 4 From http://www.uabacus.arizona.edu/Developed by Dr. L. Penny Rosenblum
Try doing 6 + 3 on your own. Say the steps! From http://www.uabacus.arizona.edu/Developed by Dr. L. Penny Rosenblum
Set a 5-bead and a 1-bead in the units column.Ask: “Can I add 3 directly?”Answer” “Yes I can.”Set three 1-beads in the units column.You now have 9 beads in the units column.Sum = 9 6 + 3 = 9 From http://www.uabacus.arizona.edu/Developed by Dr. L. Penny Rosenblum
Set three 1-beads in the tens column.Ask: “Can I add 50 directly?”Answer” “Yes I can.”Set a 5-bead in the tens column.You now have 8 beads in the tens column.Sum = 80 30 + 50 = 80 From http://www.uabacus.arizona.edu/Developed by Dr. L. Penny Rosenblum
Try doing 60 + 10 on your own. Say the steps! From http://www.uabacus.arizona.edu/Developed by Dr. L. Penny Rosenblum
Set a 5-bead and a 1-bead in the tens column.Ask: “Can I add 10 directly?”Answer” “Yes I can.”Set a 1-bead in the tens column.You now have 7 beads in the tens column.Sum = 70 60 + 10 = 70 From http://www.uabacus.arizona.edu/ Developed by Dr. L. Penny Rosenblum
Set four 1-beads in the tens column and a 5-bead in the units column.Ask: “Can I add 3 directly?”Answer” “Yes I can.”Set three 1-beads in the units column.Sum = 48 45 + 3 = 48 From http://www.uabacus.arizona.edu/ Developed by Dr. L. Penny Rosenblum
Set two 1-beads in the tens column and 7 beads in the units column.Ask: “Can I add 60 directly?”Answer” “Yes I can.”Set a 5-bead and a 1-bead in the tens column.Sum = 87 27 + 60 = 87 From http://www.uabacus.arizona.edu/Developed by Dr. L. Penny Rosenblum
Set a 5-bead in the tens column and a 5-bead in the units column.Ask: “Can I add 20 directly?”Answer” “Yes I can.”Set two 1-beads in the tens column.Sum = 75 55 + 20 = 75 From http://www.uabacus.arizona.edu/Developed by Dr. L. Penny Rosenblum
Set a 1-bead in the tens column and three 1-beads in the units column.Ask: “Can I add 20 directly?”Answer” “Yes I can.”Set two 1-beads in the ten column. • Ask “Can I add 6 directly?” • Answer” “Yes I can.”Set a 5-bead and a 1-bead in the units column.Sum = 39 13 + 26 = 39 From http://www.uabacus.arizona.edu/ Developed by Dr. L. Penny Rosenblum
Set four 1-beads in the tens column and 6 beads in the units column.Ask: “Can I add 50 directly?”Answer” “Yes I can.”Set a 5-bead in the tens column. • Ask “Can I add 2 directly?” • Answer” “Yes I can.”Set two 1-beads in the units column.Sum = 98 46 + 52 = 98 From http://www.uabacus.arizona.edu/Developed by Dr. L. Penny Rosenblum
Set two 1-beads in the hundreds column, four 1-beads in the tens column and 7 beads in the units column.Ask: “Can I add 600 directly?” Answer” “Yes I can.” Set 600 in the hundred columns. • Ask: “Can I add 0 directly?” Answer” “Yes I can.” Set 0 by tapping the silver bar in the tens column.Ask: “Can I add 1 directly?” Answer” “Yes I can.” Set 1 in the units column.Sum = 848 247 + 601 = 848 From http://www.uabacus.arizona.edu/ Developed by Dr. L. Penny Rosenblum
Set a 5-bead in the hundreds column, 6 beads in the tens column and 7 beads in the units column.Ask: “Can I add 300 directly?” Answer” “Yes I can.” Set 300 in the hundred columns. • Ask: “Can I add 20 directly?” Answer” “Yes I can.” Set 20 in the tens column.Ask: “Can I add 1 directly?” Answer” “Yes I can.” Set 1 in the units column.Sum = 888 567 +321 = 888 From http://www.uabacus.arizona.edu/Developed by Dr. L. Penny Rosenblum