few_shots: 
Example:
Concept/skill: 
Understand that by similarity, side ratios in right triangles are properties of the angles in the triangle, leading to definitions of trigonometric ratios for acute angles.

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


Answer: 
No. This problem does not directly teach how side ratios in right triangles lead to definitions of trigonometric ratios. Instead, it involves solving a trigonometric function.

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_neg_0

HS_0
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
Use the fact that 221 ÷ 17 = 13 to solve the following.
22.1 ÷ 17
2.21 ÷ 17
221 ÷ 1.7
221 ÷ 0.17
22.1 ÷ 1.7
2.21 ÷ 0.17
How did you determine where the decimal point would be in the quotients in Part (a) above? Why does that make sense?
Problem 2
Solve. Show or explain your work.
51 ÷ 6
45.2 ÷ 5
3.7 ÷ 20
14.04 ÷ 52
0.9 ÷ 0.25
27.54 ÷ 3.4


aligns: no