SAT Math 8.1 Geometry and Measurement

SAT Math 8.1 Geometry and Measurement

Additional Topics in MathCircle theorems
CirclesCircumference
Equations of Circles
GeometryCircles
LanguageEnglish Language
Product TypeSAT Math
SAT MathGeometry and Measurement

Transcript

00:20

Oh, sure… the “bicycle” traveled 2 miles. No one at all was pedaling the dang thing.

00:25

Sheesh…credit where credit is due, guys…

00:27

All right, what have we got here?

00:29

Each tire of our bike has a diameter of 26 inches… well, that should help us find the circumference.

00:37

The formula we’re looking for is 2 pi r… or pi times d, because 2r is d.

00:42

We already have our d… so...

00:44

The perimeter of each tire is 26 pi inches… or 6.8 feet.

00:53

If we weren’t already a metric conversion whiz, the problem tells us that one mile equals 5,280 feet…

01:00

…so if our bike went TWO miles, then it went 10,560 feet. Which is…a lot of feet.

01:08

All right, well… we’ve got our perimeter… now we want to know how many times each tire

01:12

can turn that 6.8 feet over the course of its 2-mile run.

01:16

We take 10,560 divided by 6.8…

01:19

…and get roughly 1,550 rotations.

01:23

Option E.

01:24

Now I suppose you’re going to give the bike all the credit for solving this problem, too, aren’t you?