Exploring Sampling Methods

Math 7

Samples & Populations Quiz #2 Review

Multiple Choice

I stood in front of VONS and asked everyone who entered what their favorite candy bar is. What kind of sampling methods did I use?

• Convenience Sampling

• Systematic Sampling

• Voluntary-Response Sampling

• Random Sampling

​I stood in front of VONS and asked everyone who entered what their favorite candy bar is. What kind of sampling methods did I use?

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This would likely be considered to be convenience sampling because it was CONVENIENT for me to gather data this way. This data is not necessarily representative of the community at large....just those that shop at VONS at 10AM on a Saturday.​

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Multiple Choice

I pulled popsicle sticks on my phone to get three students to represent us at Principal's Cabinet. What kind of sampling is this?

• Convenience Sampling

• Systematic Sampling

• Voluntary-Response Sampling

• Random Sampling

Multiple Choice

I pulled popsicle sticks to get three students to represent us at Principal's Cabinet. If all homeroom teachers use this method, will Principal's cabinet be a good representation of the entire school population?

• Yes

• No

Multiple Choice

I made a survey available on my Canvas page for any students wanting to fill out a survey about homework time. What kind of sampling is this?

• Convenience Sampling

• Systematic Sampling

• Voluntary-Response Sampling

• Random Sampling

Multiple Choice

I made a survey available on my Canvas page for any students wanting to fill out a survey about homework time. If all teachers use this method, will it be a good representation of the entire school population?

• Yes

• No

Multiple Choice

I stood in front of school and surveyed every 10th student who entered through the gate. What kind of sampling is this?

• Convenience Sampling

• Systematic Sampling

• Voluntary-Response Sampling

• Random Sampling

Multiple Choice

I stood in front of school and surveyed every 10th student who entered through the gate. Is this a good representation of our entire school population?

• Yes

• No

Multiple Choice

If I had a population of 1000 people, about how many people surveyed would be a representative sample?

• 10 - 20 people

• 800 - 900 people

• 1000 people

• 250 - 300 people

​Remember that a good, representative sample is about 25-30% of your population.

If I have 1,000 people, I want to multiply that 1,000 by 25% and 30% to find the range.


1000 x 25% = 1000 x .25 = 250
1000 x 30% = 1000 x .30 = 300

Somewhere around 250-300 people would be a good, representative sample of your population.

Multiple Choice

If I had a population of 30,000 people, about how many people surveyed would be a representative sample?

• 30,000 people

• 100 - 250 people

• 7,500 - 9,000 people

• 18,000 - 13, 500 people

Draw

Make a box-and-whisker plot of the data:

10, 11, 14, 4, 8, 12, 14, 15, 12, 10

​Here is my "oh-so-beautiful" box-and-whisker plot. Remember, there are FIVE points that are important:

Minimum

Q1

Q2/Median

Q3

Maximum​

​You're awesome, 7th Graders!!