Dividing with Base Ten Blocks

Ex # 1 23 3Finding how many subsets – repeated subtraction

• 23 is 2 longs and 3 units.

• There are no 3’s in 2 longs, so exchange the 2 longs for 20 units.

Ex # 1 23 3Finding how many subsets – repeated subtraction

• I now have 23 units.

Ex # 1 23 3Finding how many subsets – repeated subtraction

• Make groups of 3 units.

• I have 7 groups of 3 units with 2 units left over.

• 23 3 = 7 r 2

Ex # 2 23 3Finding how many in each subset – sharing

• 23 is 2 longs and 3 units.

• I want to share the pieces equally among 3 groups.

• I can’t share the 2 longs with 3 groups, so I exchange the 2 longs for 20 units.

Ex # 2 23 3Finding how many in each subset – sharing

• I now have 23 units.

• Give each group 1 unit.

Ex # 2 23 3Finding how many in each subset – sharing

• Give each group a 2nd unit.

Ex # 2 23 3Finding how many in each subset – sharing

• Give each group a 3rd unit.

Ex # 2 23 3Finding how many in each subset – sharing

• Continue this until all the units are given out.

• Each group has 7 units and there are 2 units left over.

• 23 3 = 7 r 2

Ex # 3 221 3Finding how many subsets – repeated subtraction

• 221 is 2 flats, 2 longs, and 1 unit.

• There are no 3’s in 2 flats, so exchange the 2 flats for 20 longs.

Ex # 3 221 3Finding how many subsets – repeated subtraction

• I now have 22 longs and 1 unit.

Ex # 3 221 3Finding how many subsets – repeated subtraction

• Make groups of 3 longs.

• I have 7 groups of 3 longs and 1 long and 1 unit remaining.

• Exchange the 1 remaining long for 10 units.

Ex # 3 221 3Finding how many subsets – repeated subtraction

• I now have 7 groups of 3 longs and 11 units.

Ex # 3 221 3Finding how many subsets – repeated subtraction

• Make groups of 3 units.

• I now have 7 groups of 3 longs and 3 groups of 3 units and 2 units remaining.

• 221 3 = 73 r 2

Ex # 4 221 3Finding how many in each subset – sharing

• 221 is 2 flats, 2 longs, and 1 unit.

• I want to share the pieces equally among 3 groups.

• I can’t share the 2 flats with 3 groups, so I exchange the 2 flats for 20 longs.

Ex # 4 221 3Finding how many in each subset – sharing

• I now have 22 longs and 1 unit.

Ex # 4 221 3Finding how many in each subset – sharing

• Give each group an equal number of longs.

• Each group has 7 longs and there is 1 long and 1 unit remaining.

Ex # 4 221 3Finding how many in each subset – sharing

• Exchange the 1 remaining long for 10 units.

• I now have 11 units remaining to be distributed.

Ex # 4 221 3Finding how many in each subset – sharing

• Give each group an equal number of units.

• Now each group has 7 longs and 3 units and there are 2 units remaining.

• 221 3 = 73 r 2