## Random Sampling

#### Aligned To Common Core Standard:

**Grade 7 Statistics** - 7.G.SP.A.1

What is Random Sampling? If you don't know what random sampling is, don't worry, we'll figure it out! When from a population, each and every member has an equal and probable chance of being part of the sample without any bias, it is called Random Sampling. Let us take an example. Let's say that you are going to a shop with your friends, but you don't know what to buy. When you get there, you look carefully at all the products that are available and end up purchasing a few chocolate bars along with a packet of chips, juice, and some books. This is exactly what Random Sampling is. When you reached the shop, you didn't have a clear picture of the things you wanted, and so everything had a probability of being bought.

### Printable Worksheets And Lessons

- Random or Not Step-by-step
Lesson- You will determine if a drawing was done randomly or
if there is some bias present.

- Guided Lesson -
On pretty much all accounts, we ask you to improve the experiments
that were already performed.

- Guided Lesson Explanation
- The first one is more of an answer key. There are many answers
to that one.

- Practice Worksheet
- There are many real world scenarios in this one. Many people will
need some time to complete the whole sheet.

- Matching Worksheet
- I would only recommend using this as an introductory sheet for
students new to the skill.

- Categorizing Data and Bias Five Worksheet Pack - We work on seeing data sets for what they are quantitative or qualitative.

#### Homework Sheets

We talk about ways to improve the data collection process and how to make a survey more valid.

- Homework 1 - Jack put some balls into a basket. Then, he drew 2 balls out of the basket. Is this a random sample of the balls in the basket? Why or why not?
- Homework 2 - Miller is trying to determine the best location to have his burger shop. There are 4 different districts in his city (business, garment, government, and harbor). Miller took a week to observe where people tend to gather in the business and harbor districts. Miller then decided to have his shop in the harbor district where he saw the most people gather.
- Homework 3 - Maria is trying to determine the shop location that the most people shop at. She surveys every second person coming from the shopping center. She asks them where they go to shop. What would have been an improvement in Maria research?

#### Practice Worksheets

If you read the book "Chaos", is anything ever truly random?

- Practice 1 - Jennie collected blue pens in a bag. He drew two of the five pens out of the bag. Is this a random sample of the blue pens in the bag?
- Practice 2 - Evons collected yellow egg bagels in a bag. He drew three bagels of the six bagels out of the bag. Is this a random sample of the yellow bagels in the bag?
- Practice 3 - Susan collected cell phones in a bag. She drew five of ten cell phones out of the bag. Is this a random sample of the cell phones in the bag?

#### Math Skill Quizzes

Classify the data that is being described as A) qualitative or Quantitative B) uni-variate or bi-variate C) biased or unbiased.

- Quiz 1 - Classify the data that is being described as A) qualitative or Quantitative B) uni-variate or bi-variate C) biased or unbiased.
- Quiz 2 - Maria wants to find out where the most people buy orange juice. She surveys every fourth person on a random street and asks them where they get orange juice for parties?
- Quiz 3 - Label the data samples as qualitative or quantitative.