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
Three students are partitioning a number line into fourths. Their work is shown.
Chadwick’s number line:
[IMG]
Allan's number line:
[IMG]
Dobrilla's number line:
[IMG]
Whose partitioning makes the most sense to you? Explain your reasoning.
Problem 2
a.
| Locate and label                               $$\frac{3}{4}$$                              and                               $$\frac{6}{4}$$                              . | .. image:: https://d21royfkw9g4l6.cloudfront.net/kQe2ZUaTBYoyNxM10w8iGO_7BJFW5.png |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------|
b.
| Locate and label                                 $$\frac{7}{8}$$                                and                                 $$\frac{12}{8}$$                                . | .. image:: https://d21royfkw9g4l6.cloudfront.net/kQe2ZUaTBYoyNxM10w8iGO_7BJFW5.png |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------|
c.
| Locate and label                                 $$\frac{2}{3}$$                                and                                 $$\frac{4}{3}$$                                . | .. image:: https://d21royfkw9g4l6.cloudfront.net/kQe2ZUaTBYoyNxM10w8iGO_7BJFW5.png |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------|
d.
| Locate and label                                 $$\frac{2}{6}$$                                and                                 $$\frac{7}{6}$$                                . | .. image:: https://d21royfkw9g4l6.cloudfront.net/3oblwjHOuDBzsytcrLOy5H_XO8XTR.png |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------|
e.   How did you partition the number line when you were locating the numbers
$$\frac{7}{8}$$
and
$$\frac{12}{8}$$
? Explain your reasoning.
f.   What patterns did you notice in the fractions you located?
Problem 3
Locate and label a point on the number line for
$$\frac{7}{3}$$
. Be as exact as possible.
[IMG]


aligns: no