few_shots: 
Example:
Problem/activity:
For each pair of numbers, determine if the values are equivalent. Explain your reasoning for each one.
a.
$$-0.25$$
and
$$\frac{1}{-4}$$
b.
$$-\left ( \frac{1}{4} \right )$$
and
$$\frac{-1}{-4}$$
c.
$$\frac{-1}{4}$$
and
$$-\frac{1}{4}$$


Concept/skill: 
Apply and extend previous understandings of multiplication and division and of fractions to multiply and divide rational numbers.

Answer: 
Yes. This problem involves understanding fractions and division to divide rational numbers, such as 1, -4, 4, and -1. This problem also involves an understanding of multiplication: if p and q are integers, then -(p/q) = (-p)/q = p/(-q).

Now, does the problem or activity shown below enable students to learn the full intent of the following concept or skill?

shot_info: fl_problem_001097_pos_0

7
standard_description: Display numerical data in plots on a number line, including dot plots, histograms, and box plots.
problem_activity: Activity
The goal of this activity is for students to learn how to calculate
standard deviation
(
\(\sigma\)
or
\(\sigma_x\)
) using technology. Standard deviation is a measure of variability. The work in this activity prepares students to be successful in a future Algebra 1 lesson when they have to calculate the standard deviation of data sets.
Launch
Allow students to work individually. If technology is limited, students can work in pairs. Provide access to devices that can run GeoGebra or other statistical technology. Demonstrate how to use the technology available in your classroom to compute the standard deviation of a data set. For the purposes of exploration, use the population standard deviation, often denoted
\(\sigma\)
or
\(\sigma_x\)
.
Student Facing
[IMG]
Movie A ratings on a 10 point scale:
9, 8, 10, 10, 7, 1, 8, 1, 2, 8
Movie B ratings on a 10 point scale:
9, 8, 8, 7, 9, 7, 7, 9, 7, 8
Restaurant A ratings on a 100 point scale:
88, 87, 89, 90, 87, 85, 88, 91, 86, 86, 88, 89
Restaurant B ratings on a 100 point scale:
90, 65, 89, 50, 94, 93, 95, 95, 75, 70, 88, 89
Calculate the mean and standard deviation for each data set.
Based on these statistics, which movie and restaurant would you choose? Explain your reasoning.
Student Response
Teachers with a valid work email address can
click here to register or sign in
for free access to Student Response.
Activity Synthesis
Select students to share their solutions. Ask students how the standard deviation influenced their preferred movie and restaurants.


aligns: no