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# A Simple Balance

Media Type:
Video

Running Time: 2m 33s
Size: 7.3 MB

or

Source: Cyberchase: “A Battle of Equals”

### 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, the CyberSquad is attempting to save Sensible Flats from disaster. In order to gain access to the machine they need, the CyberSquad must unlock it by figuring out the correct number code. In order to do this they have to balance a scale using two weights.

Connections

Everyday Math (2004)
Teacher Lesson Guide: pp. 189-193
Teacher Reference Manual: pp. 49, 277-283
Student Reference Book: pp. 207-213

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 seen a simple balance? If you put a one-pound weight on one side and a two-pound weight on the other side, what would happen? What would happen if you put a three-pound weight on one side and a three-pound weight on the other side? How would you describe that using numbers and symbols?

Focus: In this segment, the Cybersquad has to get a scale to balance completely. How do they manage to do this? What does Jackie say an “equals” sign really means?

Follow Up: What did the CyberSquad find out about balancing the scale? What happened to the balance when the weights were not equal to each other? Can you write an equation that describes how the scale finally balanced?

Transcript

DIGIT: There's a number lock on the lever. It won't budge till we enter the right code numbers.

INEZ: Is that what Hacker did to release the cyberstatic?

DIGIT: He had to! It's the only way the lock works.

JACKIE: Where do we get the numbers?

DIGIT: Off these weighty things. I watched the Doc do it once. He picked two weights - put one on each side of this scale and... INEZ: And what?

DIGIT: And uh, that's all I remember - except that something has to balance. Does, uh,that help?

JACKIE: Yeah, it helps! A balance scale to shows when two things weigh the same.

DIGIT: I knew that.

INEZ: We'll show you - maybe then you'll remember more. You and Matt put one weight on each side of the scale - and don't let me see the numbers!

INEZ: The numbers aren't the same.

DIGIT: How'd she know that?

MATT: Because the scale doesn't balance. It tipped down this way...so the weight on this side has to be heavier.

JACKIE: Which means the numbers on this weight is greater.

DIGIT: You're right! Eighteen is definitely more than nine. Even I know that!

JACKIE: So when Doctor Marbles said the weights had to balance - it was clue! Now do you remember what happened next?

DIGIT: Yes! I remember! He wrote the numbers that balanced in here!

MATT: Two places for the numbers - and an equalssign between them.

JACKIE: Equals means that two numbers have to have the same value - and that's just what the balance tells us!

INEZ: So we need two weights with the same numbers.

MATT: Here's a three! Is there another three down there?

JACKIE: Uh-uh! No threes!

DIGIT: Here's a five? Anyone got another five? Lookin for a five!

JACKIE: Got it!

JACKIE: It balances! Five equals five!

MATT: That must be the number code! I'll write it in.

DIGIT: Hold it!

DIGIT: I just remembered! We can't use just any old marker to enter the code! The Doc used this special one!

INEZ: Hurry! Sensible Flats is almost Static Flats!

MATT: Five on the left equals five on the right.

VOICE: Security access permitted.

KIDS: We did it!

MATT: The satellite is pulling the cyberstatic back in!

MATT: Sensible Flats is saved!

Standards

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