Geometric Probability
M217 - Geometry
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Probability - The chance that an event
will occur (a # between 0 and 1).
Geometric Probability – Probability
involving geometric measures, such
as length or area.
Probability and Length
Length of CD
P(point K is on CD ) =
Length of AB
A
C
D
B
Probability and Area
P(point K is in region M) =
J
M
Area of M
Area of J
Example
F
0
R
1
2
3
E
4
5
6
7
M
8
D
9 10 11 12
Find the probability that a point K, selected
randomly on FD , is on the given segment.
1.
FR
2.
RM
3.
ER
4.
DF
Example
14
4
10
Find the probability that a randomly
chosen point in the figure lies in the
shaded region.
8
Example
12
12
Find the probability that a randomly
chosen point in the figure lies in the
shaded region.
Time problems
If you knew there was going to be a fire drill at
some point during our school day, what is the
probability that it happens before 3rd hour?
School Day: 7:30 AM – 2:45 PM
3rd hour begins @ 9:20 AM
Homework
WS 11.6A
and 11.6B