Chapter 4.6

Question 1

What is Fundamental Counting?

Answer 1

When repeats are allowed you multiply the possibilies for each step; Options^Selections

e.g. 6 places: 3 letters and 3 numbers=10^3X26^3

pg. 171

Question 2

What is a factorials?

Answer 2

Symbol=!; means-n!=nx(n-1)x(n-2)…
If n things are arranged in order, the number of possible arrangements is: n!
use when order matters and all are selected
-Calc: Math->PRB->!or4

e.g. 4!=4x3x2x1=24

pg. 173

Question 3

What is a Permutation?

Answer 3

Selected
order matters
no repeats ;
nPr
n=objects, r=selections
P for perfect order

Calc: Math->PRB->nPr or 2

pg. 175

Question 4

What is a Combination?

Answer 4

Selected
no repeats
no order;
nCr
n=objects, r=selections
C for ‘who cares’ about order or comb pizza order doesn’t matter

Calc: Math->PRB->nCr or 3

pg. 177

Question 5

What is a complement of an event?

Answer 5

Complement Symbol=Abar
all outcomes that are NOT ‘A’
probability that an event will NOT occur

P(Abar)=1-P(A) and P(A)=1-P(Abar)

pg. 190