Activities/Abacus/Worksheet: Difference between revisions
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===The Caacupé abacus=== | ===The Caacupé abacus=== | ||
Load the Caacupé abacus | Load the Caacupé abacus [[File:Abacuscaacupe.jpg]] | ||
It can represent negative whole numbers and fractions. 1/2 can be represented as 10 - 9 - 2/3 + 1/6 | It can represent negative whole numbers and fractions. 1/2 can be represented as 10 - 9 - 2/3 + 1/6 | ||
Revision as of 23:34, 4 April 2011
Fractions
The Fraction abacus
Start Abacus 
,
select the Fraction abacus.
Slide one of the 1/2 beads to represent 1/2
Another way to represent 1/2 is to slide half of another string of fraction beads, for example slide 2 of the 1/4 beads. That is (2 x 1)/4 = 2/4 = 1/2
How many ways can you make 1/2, remember you can use 2 strings eg. 1/3 + 1/6 = 1/2
If using just one string, only some of the strings of beads can be used to make 1/2. Which ones? Why?
How do you know if you have found all the solutions?
Find all the ways to make 1/3 and 2/3
The Caacupé abacus
Load the Caacupé abacus 
It can represent negative whole numbers and fractions. 1/2 can be represented as 10 - 9 - 2/3 + 1/6
How many different ways can you represent 1/2 , 1/3, 2/3
How do you know when you have found them all?
see the answersheet