standard_description: Add and subtract fractions with unlike denominators (including mixed numbers) by replacing given fractions with equivalent fractions in such a way as to produce an equivalent sum or difference of fractions with like denominators. For example, 2/3 + 5/4 = 8/12 + 15/12 = 23/12. (In general, a/b + c/d = (ad + bc)/bd.)
problem_activity: Problem 1
Someone sorted some shapes as shown below.
[IMG]
a.   What is similar about the two groups of figures? What term(s) can we use to describe all of the shapes?
b.   What is different about the two groups of shapes?
Problem 2
Decide whether each of the following statements are true or false. If it is false, rewrite the statement so that it is true.
a.   A trapezoid is always a quadrilateral.
b.   A quadrilateral is never a trapezoid.


aligns: no