Download 1. Rebekah has a dilemma. It is the first day of school and she does

Basic Counting Principle
Steps:
1) Decide how many events there are.
2) With each event how many possible outcomes.
3) Multiply the individual independent events together.
1. Rebekah has a dilemma. It is the first day of school and she does not know what to wear!
She has 3 skirts to choose from and 4 blouses, how many possible outfits does she have to
choose from?
a) 7
b) 3
c) 4
d) 12
2. You and your friends are ordering a pizza. You get to choose the size(Mega, Huge, or
Not-so-Huge), the type of sauce(Red or White), the amount of cheese(Cheese-less, Normal
or Xtra Cheesy), and 1 topping from topping list(15 items). How many different pizzas
could you possibly order?
a) 60
b) 23
c) 270
d) 1080
In Combinations, order does not matter.
n
The formula for a combination is
Cr 
n!
r ! n  r !
3.Ten different colored socks are in a drawer. Without looking, two socks are removed.
What is the total number of combinations?
a. 45
b. 90
c. 1
d. 60
4.Kate went to the store and bought a package of refrigerator magnets each with a different
word on them. The package contained fifteen words. How many ten word sentences can be
made using the magnets?
e. 360,360
f. 3003
g. 3,628,800
h. 120
5. Baskin Robbins has 31 flavors, or so they say.  If you only have enough money to
buy two scoops, how many combinations could you order?
a. 2
b. 930
c. 465
d. 404
A dependent event “changes” or “depends” on a previous event.
Decide whether the event is dependent or independent.
6. Flip a coin, and then flip the same coin.
7. Select a card from a deck, keep it, and pick another card.
Remember: Probability is the likelihood that something will happen.
It is usually written as a fraction(ratio) and sometimes as a decimal(percentage).
P(E) = # of favorable outcome
Total # of outcomes
8. If a dart hits the target at random,
what is the probability that it will land
in the shaded region?
3.2 in
3.2 in
5 in
10. A drawer contains 7 black socks,
3 gray socks, and 2 blue socks.
Without looking, you draw out a sock
and then draw out a second sock
without returning the first. What is
the probability that the two socks are
a matching pair?
49
144
7
b.
22
25
66
25
d.
72
a.
10 in
2
1
c.
3
2
1
1
b.
d.
3
4
9. If a dart hits the target at random,
what is the probability that it will land
in the shaded region?
a.
6 in
2 in
1
3
7
b.
16
a.
1
9
1
d.
4
c.
c.
11. What is the probability that a
randomly dropped marker will fall in
the unshaded region?
14
15
1
b.
15
1
16
15
d.
16
a.
c.
12. A bag contains 3 green marbles
and 5 purple marbles. One marble is
drawn at random and not replaced.
Then a second marbles is drawn.
What is the probability that the first
marble is purple and the second one is
green?
15
56
15
b.
64
a.
5
3
3
d.
5
c.