Likelihood & Simple Probability
A standard 6-sided number cube is rolled. Describe an event that is absolutely certain to happen.
Rolling a number between 1 and 6 (or rolling a number less than 7).
A lunch menu lets you pick 1 food item and 1 drink. If there are 5 food choices and 7 drink choices, how many total combinations can you make?
35 combinations (5x7=35).
If the probability of a basketball team winning is 4/6, what tool is best to simulate 7 games: a standard 6-sided die, or a coin?
A standard 6-sided die
The principal wants to know what students think about school lunch. Why is it a bad idea to only survey students who bring their lunch from home?
It is a biased sample (they don't eat school lunch, so it doesn't represent everyone).
Class X has test scores ranging from 60 to 100. Class Y has test scores ranging from 80 to 95. Which class has greater variability (is more spread out) in its results?
Class X (Range of 40 vs. Range of 15).
Which of the following numbers represents the probability of an event that is very likely to occur: 0.05, 0.50, or 0.91?
0.91
You drive past a stoplight that can be Red (R) or Green (G). If you drive past it two mornings in a row, list the 4 possible outcomes in the sample space.
RR, RG, GR, GG
A spinner has a 1/4 chance of landing on yellow. If you spin it 100 times, how many times do you expect it to land on yellow?
25 times (1/4 x 100=25)
To get a fair, representative sample of the whole school, is it better to survey 3 random students from every homeroom, or just survey the 7th graders?
3 random students from every homeroom.
More spread out-More variability
What is the formula for probability?
P(a)=number of favorable outcomes/total number of outcomes
A coin can land on Heads (H) or Tails (T). If you flip it two times, what is the probability that it lands on Heads bothtimes (HH)?
1/4
In a survey of 50 people, 20 said baseball was their favorite sport. If you survey 250 people instead, how many would you predict like baseball?
100 people (20/50=0.4, 0.4x250=100)
In a dot plot tracking how many video games students own, there are 5 dots sitting directly on top of the number 0. What do those 5 dots mean?
It means 5 students own exactly 0 video games.
What is Mrs. Ortell's dog's name? (Hint it's close to a type of flower)
Rosie <3
On a spinner, the probability of landing on blue is 0.15. Describe the likelihood of landing on blue using a word like likely, unlikely, or certain.
Unlikely (but not impossible).
A menu offers Pizza, Burgers, or Tacos for food, and Juice or Milk for drinks. If Dre picks at random, what is the probability he gets a Burger and Milk?
1/6 (1 favorable combo out of 6 total combos).
You want to simulate a 2/3 probability. You decide to use a spinner with 12 equal sections. How many sections must say "Win"?
8 sections (8/12=2/3)
True or False: A small sample graph can be considered a "representative sample" if its overall shape and distribution look very similar to the large population graph.
True
Class X has a median test score of 85. Class Y has a median test score of 92. Which class has generally higher test scores?
Class Y
Out of 50 people surveyed at a pet store, 35 own dogs, 10 own cats, and 5 own lizards. What is the probability that the next customer owns a lizard? (Simplify if you can!)
1/25 (since 5/50=1/25)
Sarah flips a coin and spins a spinner with 10 equal sized pieces. How many total outcomes are in this sample space?
20 outcomes (2x10=20).
1000 point question: What is Mrs. Ortell's favorite TV show of all time?
(Hint: it was made by Nickelodeon)
AVATAR THE LAST AIRBENDER
A gym teacher wants to know the favorite sport of all middle schoolers. Method A: Survey every 5th student entering the gym. Method B: Survey the varsity basketball team. Which method provides the best representative sample?
Method A (it is random and doesn't target a specific group).
Find the mean, median, and IQR: 2,4,5,8,10,12,13,16,20
Mean=10, Median=10, IQR=10
Q1=4.5, Q3=14.5, IQR=14.5-4.5=10