Math Basics: The Visual Approach to Equivalent Ratios

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Transcript

00:26

Fransel and Stetl, who had always boasted clear, unblemished flesh… [Fransel and Stetl cursed by witch in the woods]

00:31

…suddenly found themselves looking a bit like their tormentor. On a bad day.

00:35

In addition, the witch cursed the children with a desire to use strip diagrams on a regular basis. [Fransel and Stetl walking like zombies by a house]

00:41

Talk about cruel and unusual. As soon as Fransel and Stetl got home, they

00:46

created the following strip diagram: As you can see, Fransel’s diagram is divided [Fransel and Stetl drawing a strip diagram]

00:52

into 8 rectangles, while Stetl’s was divided into 6 rectangles.

00:57

We can also tell that there is a total of 98 zits that have popped up since their unexpected encounter.

01:02

How many zits did each child get? Well, when dealing with strip diagrams, the

01:07

important thing to remember is that all rectangles are created equal. [3 equal rectangles of a strip diagram]

01:12

Just because this one looks bigger than this one…

01:14

…doesn’t mean it represents any more of… whatever it is we’re measuring.

01:19

So really, we’ve got 14 total rectangles, and we have to divide the 98 zits evenly between them.

01:26

Looks like a simple division problem:

01:28

98 divided by 14 is… 7.

01:31

So now we know each rectangle represents 7 zits…

01:35

We can multiply by 8 to get Fransel’s total – 56…

01:39

…and by 6 to get Stetl’s total – 42.

01:42

Just to double-check our work… does 56 plus 42 equal 98? [Fransel and Stetl's total of zits per rectangle]

01:47

You bet it does. Of course, none of this busy work distracts

01:50

the children for one second from the fact that their appearances have been altered. [Fransel and Stetl running over to a mirror]

01:54

Fortunately for them, their other cousins, Wansel and Spaetzl, have just been cursed

01:59

by yet another witch with a lifetime supply of Clearasil… [Wansel and Spaetzl appear with a tube of clearasil]