## Lightning

## Opening

# Lightning

Think about this question, and then discuss your ideas with a partner.

- How likely do you think it is that your house will be struck by lightning this year?

Think about this question, and then discuss your ideas with a partner.

- How likely do you think it is that your house will be struck by lightning this year?

Think about what makes one event more likely to occur than another event.

Use the Likelihood Line interactive to help you think about likelihood.

- Where on the line would you place the likelihood of your house being struck by lightning? Put a mark at that point.
- Can you think of an event that is impossible—that cannot happen? Write an example of one.
- Can you think of an event that is certain? Write an example.
- Are there events you can think of that are equally likely to happen as to not happen? Write an example.

INTERACTIVE: Likelihood Line

For each event, use the Likelihood Statements interactive to mark the line with the letter of the event to indicate its likelihood.

What is the likelihood that...

a. It will rain tomorrow?

b. Someone will be absent?

c. The temperature will be above 60°F?

d. You will send a text sometime today?

e. Your teacher will assign homework?

f. You will buy lunch at school?

g. You will get a high score on the next math test?

h. Out of all the students at your school, you will be chosen at random to win a prize?

i. Out of all the students at your school, you will not be chosen at random to win a prize?

j. Out of all the students in your class, you will be chosen at random to win a prize?

k. Out of all the students in your class, a girl will be chosen at random to win a prize?

INTERACTIVE: Likelihood Statements

Choose two events from the list. What is the likelihood they will both happen? Use the Two Events Likelihood Line interactive to mark the likelihood on the line.

a. It will rain tomorrow.

b. Someone will be absent.

c. The temperature will be above 60°F.

d. You will send a text sometime today.

e. Your teacher will assign homework.

f. You will buy lunch at school.

g. You will get a high score on the next math test.

h. Out of all the students at your school, you will be chosen at random to win a prize.

i. Out of all the students at your school, you will not be chosen at random to win a prize.

j. Out of all the students in your class, you will be chosen at random to win a prize.

k. Out of all the students in your class, a girl will be chosen at random to win a prize.

INTERACTIVE: Two Events Likelihood Line

Take notes about how your responses compared to those of your classmates.

As your classmates present, ask questions such as:

- What statement about likelihood could you make for each event? (For example: It is very unlikely that I would be chosen at random for a prize.)
- How did you decide where to place a mark for each event?
- What is the likelihood that both events, "You will be chosen at random to win a prize" and "You will not be chosen to win a prize," will happen?
- How does the likelihood of the opposite of each event compare to the likelihood of the original event? (For example, “It will not rain tomorrow” versus “It will rain tomorrow” and “The temperature will be below 60°F” versus “The temperature will be above 60ºF”)?

Write a reflection about the ideas discussed in class today. Use the prompts below if you find it to be helpful.

**In the next 24 hours, here is a list of some things that are likely to occur…**

**In the next 24 hours, here is a list of some things that are unlikely to occur...**