options: Recognize and represent proportional relationships between quantities.

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.

Use proportional relationships to solve multistep ratio and percent problems. Examples: simple interest, tax, markups and markdowns, gratuities and commissions, fees, percent increase and decrease, percent error.
problem_activity: Problem 1
Shade in the grids to represent the following fractions:
|                                  a.                     $${30\over 100}$$                                  |                                  b.                     $${3 \over100}$$                                   |                              c.                     $${{1\over3}\over 100}$$                               |
|------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------|
| .. image:: https://d37su8u1z9ynie.cloudfront.net/uploads/2017/12/18/screen-shot-2017-12-18-at-40254-pm.png | .. image:: https://d37su8u1z9ynie.cloudfront.net/uploads/2017/12/18/screen-shot-2017-12-18-at-40254-pm.png | .. image:: https://d37su8u1z9ynie.cloudfront.net/uploads/2017/12/18/screen-shot-2017-12-18-at-40254-pm.png |
Problem 2
Fill in the chart below to represent equivalent fractions, decimals, and percentages.
| **           Fraction          ** | **           Decimal          ** |   **           Percent          **   |
|-----------------------------------|----------------------------------|--------------------------------------|
|          $$\frac{1}{4}$$          |                                  |                                      |
|                                   |               0.5                |                                      |
|                                   |                                  |                 20%                  |
|          $$\frac{1}{3}$$          |                                  |                                      |
|                                   |               0.05               |                                      |
|          $$\frac{3}{8}$$          |                                  |                                      |
|                                   |               1.3                |                                      |
|                                   |                                  | $$\frac{1}{2}$$                    % |
Problem 3
Use mental math to answer the questions below.
a.
What is 50% of 20?
What is 25% of 48?
What is 10% of 125?
What is 5% of 50?
b.
6 is 50% of what number?
10 is 25% of what number?
9 is 10% of what number?
c.
21 is what percent of 210?
450 is what percent of 900?
20 is what percent of 80?
30 is what percent of 20?


correct_option_index: 2