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To return to the previous page, use the back button on your browser. Multiplication using Multibase Arithmetic Blocks A child can be taught the multiplication algorithms using MAB. The use of these blocks is illustrated with examples. Click below to see the following examples. | Multiplication by ones | Multiplication by tens | Example 1: 3 X 6 Three groups of 6 will be as shown below. Now there are more than 10 blocks. 10 of these can be traded for one long or ten. So the answer is 18. Example 2: 23 X 4 23 is represented by 4 groups of 23 will be Now there are 8 longs and 12 ones. At this stage, 10 ones can be traded for 1 long, giving 9 longs and 2 ones. 4 groups of 23 become 9 longs and 2 ones, giving 92. Understanding how numbers move into adjacent place value columns when multiplied by ten is a crucial fact underlying the multiplication algorithms. The formal algorithms are built from this basic information. Example 3: 10 X 2 Start with 10 groups of 2 10 ones can be traded for a long and then the other 10 ones can be traded for another long. Thus 10 groups of 2 become 2 tens or twenty. Example 4: 10 X 32 32 is 3 tens and 2 ones. That is 3 longs and 2 ones. 10 groups of 32 will be Now there are 30 longs and 20 ones. 10 longs can be traded for a flat. 30 longs can be traded for 3 flats. And the 20 ones can be traded for 2 longs. So in all we have 3 flats and 2 longs. The answer is 320. |
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