standard_description: Use numbers expressed in the form of a single digit times an integer power of 10 to estimate very large or very small quantities, and to express how many times as much one is than the other. For example, estimate the population of the United States as 3 × 108 and the population of the world as 7 × 109, and determine that the world population is more than 20 times larger.
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?


aligns: no