few_shots: 
Example:
Concept/skill: 
Prove the addition and subtraction formulas for sine, cosine, and tangent and use them to solve problems.

Problem/activity:
Find the general solution for:
$${\mathrm{cos}\left({\pi\over2}+x\right)=\mathrm{tan}{\pi\over4}}$$


Answer: 
Yes. An initial step when solving for x in this problem requires the use of the addition formula for cosine on the left side of the equation.

Now, determine whether the following problem or activity can enable students to understand the concepts or skills in the provided description.

shot_info: fl_problem_001894_pos_0

HS_0
standard_description: Solve real-world and mathematical problems by writing and solving equations of the form x + p = q and px = q for cases in which p, q and x are all nonnegative rational numbers.
problem_activity: Problem 1
Represent each fraction as a percent by completing the table. Use the two double number lines below to show your work.
| Fraction |   |   |   |   |   |
|----------|---|---|---|---|---|
| Percent  |   |   |   |   |   |
[IMG]
Problem 2
Answer the questions below using mental math. Use your double number lines from Anchor Problem 1 if you need to.
a.   What is
$$\frac{1}{2}$$
of 20?
b.   What is 50% of 20?
c.   What is 10% of 60?
d.   What is 20% of 60?
e.   What is
$$\frac{1}{4}$$
of 48?
f.   What is 25% of 48?
g.   What is 75% of 48?
h.   What is 10% of 125?
i.   A textbook that costs $36 is on sale for 25% off. How much money will you save?
Problem 3
Answer the questions below using mental math. Use your double number lines from Anchor Problem 1 if you need to.
a.   5 is 50% of what number?
b.   12 is 10% of what number?
c.   15 is 25% of what number?
d.   30 is 75% of what number?
e.   400 is 20% of what number?
f.   A coat is on sale for 10% off. You save $18. What was the original price of the coat?
Problem 4
Answer the questions below using mental math. Use your double number lines from Anchor Problem 1 if you need to.
a.   24 is what percent of 240?
b.   350 is what percent of 700?
c.   20 is what percent of 80?
d.   30 is what percent of 40?
e.   80 is what percent of 80?
f.   You saved $4 on a book that originally cost $16. What percent of the original cost did you save?


aligns: no