Answer:
a: true; b: true; c: false
Explanation:
The common denominator of the fractions 1/3 and 1/4 can be 12. 15a is true.
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1/4 = 3/12, so 15b is true.
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The difference 2 1/3 -1 1/4 is the difference 2 4/12 - 1 3/12 = 1 1/12. This is not the same as 1 1/6. 15c is false.