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# Estimating Time from Rate

Media Type:
Video

Running Time: 3m 09s
Size: 8.7 MB

or

Source: Cyberchase: "Snow Day to be Exact"

### Collection Developed by:

Collection Credits

### Collection Funded by:

Funding for the VITAL/Ready to Teach collection was secured through the United States Department of Education under the Ready to Teach Program.

In this video segment from Cyberchase, Harry is in line to buy a ticket to a Broadway show, but the line is moving very slowly. He is not sure if the line is moving fast enough for him to get to the front and buy his ticket before the ticket window closes. Finally, Harry makes an estimate to decide whether he should stay in line or go see a movie instead.

Connections

Everyday Math (2004)
Teacher Lesson Guide, pp. 99-100,
291-302
Student Reference, pp. 154-158
Math Journal, pp. 35, 118-124
Math Master, pp. 77, 284-285

Investigations/Scott Foresman (2006)
Investigation 1, Sessions 1-3, pp. 4-22
Packages and Groups
Investigation 2, Sessions 2 and 3, pp. 24-27
Investigation 3, Sessions 4-6, pp. 46-50
Landmarks in the Thousands
Investigation 3, Sessions 3-5, pp. 43-63

Teaching Tips

Here are some Frame, Focus and Follow-up suggestions for using this video in a math lesson.

What is Frame, Focus and Follow-up?

Frame: Have you ever had to estimate how long something will take? Give an example. Sometimes estimates can involve thinking about not only time, but distance as well. Have you heard of the term "rate"? Rate is a specific kind of ratio, in which two measurements are related to each other, such as time and distance. How do you think airlines might go about estimating the time it takes to fly from one city to another?

Focus: As you watch this segment, think about why Harry feels he has to make an estimate. Then, consider how he goes about making his estimate. What information does he gather to help make an accurate estimate?

Follow Up: Why did Harry time how long it took the line to move across one sidewalk square? Did he use multiplication? How and why? How would you go about estimating how long you might have to wait for a haircut in a barber shop? What information would you need to gather in order to make a good estimate?

Transcript

HARRY: I love Broadway theater. The bright lights, the actors, music. Give my regards to Broadway. But as much as I love seeing Broadway shows, they do cost a lot of money. This is a great place where you can buy tickets at a discount for the next performance. Hey, that's on my list of things I want to see. Wow, that's a hot ticket. I better get in line.

Excuse me is this the end of the line?

MAN #1: No, sir, it's way down there. All the way down.

HARRY: Have you been waiting long?

WOMAN #1: No, we just got here, too.

HARRY: Is the line moving quickly?

WOMAN #1: We just got here.

HARRY: This line is certainly moving slowly. How many people are in front of us?

MAN #2: A lot man. A lot.

HARRY: Duh. Was that guy in front of us or did he sneak in? Because if he snuck in then you tell him that that's just not very nice.

MAN #2: No, I think he was there.

HARRY: The ticket booth closes at six o' clock. That's in twenty-one minutes, and I hope I can get to the head of the line before all the tickets are sold out.

How fast do you think this line's moving?

WOMAN #2: Not fast enough!

HARRY: If I can make it to the window before it closes I get to see a Broadway show at a bargain price. Maybe. Then again I could cross the street and see a movie that starts in a few minutes. Guaranteed. My problem is that if I wait too long I may not get a chance to do either.

People, this line would move a lot faster if you had your money out. OK? Thank you for your cooperation. It's greatly appreciated.

I told them how to make the line move faster.

WOMAN #3: Yeah, I heard.

HARRY: This line is moving so slowly. I need a way to figure out how fast this line is moving. If it isn't moving fast enough I can't get my ticket, and I should just go to the movies now. Is it just me or does it seem like this line is moving slowly?

WOMAN #4: It's moving extremely slowly.

HARRY: That's what I thought.

I'm going to time how long it takes to walk from here to there. Across one sidewalk square.

Oh excuse me.

WOMAN #4: What time is it?

HARRY: Five minutes. Well, it's moving. Slowly, but it's moving. Wait a second, if it took five minutes to cross one sidewalk square. Then all I need to do is figure out how many more sidewalk squares there are between here and the ticket window. One, two, three, four. OK, there are four sidewalk squares left. If the line keeps moving at the same speed: five minutes per sidewalk square, then five minutes times four sidewalk squares is twenty minutes, and that's not fast enough. The window closes in fifteen minutes. Next time I'll come earlier. This time I'm off to see a movie.

Standards

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