standard_description: Compute unit rates associated with ratios of fractions, including ratios of lengths, areas and other quantities measured in like or different units. For example, if a person walks 1/2 mile in each 1/4 hour, compute the unit rate as the complex fraction 1/2/1/4 miles per hour, equivalently 2 miles per hour.
problem_activity: Problem 1
Two different students solved the problem
$$1\frac9{10}+5\frac4{10}$$
below. Study their work and determine whether the strategy they used works.
|                          **             Student A            **                          |                          **             Student B            **                          |
|------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------|
| .. image:: https://d21royfkw9g4l6.cloudfront.net/uploads/2022/03/24/g4mathu5l14_at1a.png | .. image:: https://d21royfkw9g4l6.cloudfront.net/uploads/2022/03/24/g4mathu5l14_at1b.png |
Problem 2
Two different students solved the problem
$$4\frac38-3\frac68$$
below. Study their work and determine whether the strategy they used works.
|                           **            Student C           **                           |                           **            Student D           **                           |
|------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------|
| .. image:: https://d21royfkw9g4l6.cloudfront.net/uploads/2022/03/24/g4mathu5l14_at2a.png | .. image:: https://d21royfkw9g4l6.cloudfront.net/uploads/2022/03/24/g4mathu5l14_at2b.png |
Problem 3
Solve.
| $$1+\frac{5}{12}$$                          $$\frac{11}{12} + \frac5{12}$$ | $$8+4\frac36$$                          $$7\frac56+4\frac36$$ | $$1\frac1{10}-\frac1{10}$$                          $$1\frac1{10}-\frac2{10}$$                          $$1\frac1{10}-\frac4{10}$$ | $$6\frac15-5$$                          $$6\frac15-4\frac45$$                          $$6\frac15-4\frac25$$ |
|----------------------------------------------------------------------------|---------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------|


aligns: no