Vocab Terms
General term that describes how likely something is to happen.
Probability
What is the theoretical probability of flipping a coin and landing on heads?
P(heads)=1/2=50%
Marcus is practicing free throws in basketball. He takes 25 shots and makes 17 of them. What is the experimental probability of Marcus making a free throw?
17/25=68%
How many outcomes are there to flipping a coin twice?
S={HH,HT,TH,TT}
What is the probability of flipping exactly one tails?
P(exactly one tails)=2/4=1/2=50%
Experimental probability
What is the theoretical probability of rolling a dice and getting a 4?
P(4)=1/6=about 16.7%
Over the past 20 days, it rained on 7 days. What is the probability that it does NOT rain?
13/20=65%
How many combinations can you create with 4 pairs of pants and 3 t-shirts?
12
(11,12,13,21,22,23,31,32,33,41,42,43)
The sample space below represents the outcomes of two friends choosing flavors of smoothy: banana, strawberry, pineapple.
S={BB,BS,BP,SB,SS,SP,PB,PS,PP}
What is the probability that both friends choose the same flavor?
P(same flavor)=3/9=1/3= about 33%
The term used to describe an event made up of 2 or more events
Compound event
In a marble bag containing 4 blue marbles, 7 red marbles, 5 yellow marbles, and 4 green marbles, what is the probability of choosing a green marble?
P(green)=4/20=1/5=20%
Jasmine has a bag with red, blue, and green candies. She doesn’t know how many of each color there are, so she runs an experiment. She grabs one candy at a time (without looking), records the color, and puts it back.
After 40 trials, she records:
What is the experimental probability of choosing a red candy?
18/40=9/20=45%
What is the sample space when spinning a spinner with red, blue, and green sections and flipping a coin?
S={RH,RT,BH,BT,GH,GT}
The sample space below shows the outcomes to spinning a spinner (red, blue, green) and flipping a coin.
S={RH,RT,BH,BT,GH,GT}
What is the probability that the outcome includes landing the spinner on red or green?
P(landing on red or green)=4/6=2/3= about 67%
This term describes the rules we used when solving equations (getting the variable by itself).
Inverse Operations
In a marble bag containing 4 blue marbles, 7 red marbles, 5 yellow marbles, and 4 green marbles, what is the probability of choosing a blue or yellow marble?
P(blue or yellow)=9/20=45%
Lena rolls a standard six-sided die 36 times. She records how many times she rolls a each number:
What is the probability of not rolling a 4?
31/36=about 86%
What is the sample space of spinning a spinner with red, blue, and green sections and rolling a 6-sided number cube?
S={R1,R2,R3,R4,R5,R6,B1,B2,B3,B4,B5,B6,G1,G2,G3,G4,G5,G6}
What is the probability of rolling a 1 AND an even number when rolling two dice?
P(1 and even)=6/36=1/6= about 16%
Percent
The letters below are put on tiles and thrown into a bag:
A, A, A, B, C, D, E, F, G, H, L, L, M, N, O, O, P, Q, R, S, S, T, T, T, X
Find the theoretical probability of pulling a vowel out of the bag.
P(vowel)=6/25=24%
A student spins a spinner divided into sections labeled A, B, and C. After spinning it 30 times, the results are:
Predict how many times you would land on A out of 100 spins.
9/30=x/100
30=x
30 times landing on A
What is the sample space of 3 children being boys or girls
S={BBB,BBG,BGB,BGG,GBB,GBG,GGB,GGG}
What is the probability of rolling two even numbers when rolling two dice?
P(two even numbers)=9/36=1/4=25%