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Passport to Advanced Math Videos 52 videos

Multiplying Polynomials to Find an Unknown Constant
3 Views

In the equation above, if a, b, and c are all constants, what is c?

Recognizing Polynomial Factors
4 Views

When x = 12, a certain polynomial, y, equals 0. Which of the following must be true about the polynomial y?

SAT Math 1.5 Algebra and Functions
218 Views

SAT Math 1.5 Algebra and Functions. If f (x) = x2 - 16 and g(x) = x4 - 256, what is f of x divided by g of x?

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SAT Math 5.5 Numbers and Operations 182 Views


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Description:

SAT Math 5.5 Numbers and Operations

Language:
English Language

Transcript

00:02

Here’s your shmoop du jour, brought to you by Handshakes.

00:06

The best way to pass along bacteria to someone you’ve just met.

00:09

Six people are in a room.

00:11

If everyone shakes hands one time with each other, how many handshakes take place?

00:18

Okay, so either some important business deal is about to go down…

00:21

…or else the annual Sweaty Palm Convention is in town.

00:24

Purell, anyone?

00:26

All right – we’re looking for the total number of handshakes.

00:29

First, each of the 6 people has to shake hands with the 5 other people.

00:34

To count these handshakes, let’s multiply 6 by 5... 30.

00:39

Oops. By doing that, we’ve over counted… by a lot.

00:43

With this method, we’re basically counting person A shaking hands with person B as one handshake

00:49

and person B shaking hands with person A as a totally separate handshake.

00:54

In reality, when 2 people shake hands with each other, that only counts as 1 handshake.

01:00

To be more specific, our number is actually double the real number of handshakes actually happening,

01:06

so divide that 30 by 2 and get 15.

01:09

That’s a lot of handshaking.

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