Making 50%
People say "50/50" all the time. In math, what does this really mean?
It means 1 whole 50 pieces out of 50 pieces.
There are 2 yellow marbles, 4 blue marbles, and 6 red marbles in a bag. What is the probability of pulling out a blue marble?
4/12 or 1/3
A spinner is split into 4 sections. Does that always mean that the sections are equal and that all the outcomes have an equal chance? WHY?
No.
One section could be bigger than the others or 2 sections could have the same label.
You use colored cubes to decide between 3 different options. What is a fair way to get each outcome using these cubes?
Have three different colors and assign each option a color. Then put them in a bag and draw one out.
What is the difference between theoretical and experimental probability?
Theoretical is what should happen (based on the information) and Experimental is what does happen (when you do the experiment)
A bag contains one green marble, two yellow marbles, four blue marbles, and five red marbles.
What is the theoretical probability of randomly drawing a blue marble from the bag?
4/12 or 1/3
How do you turn a fraction into a percent?
Divide the top by the bottom and multiple by 100.
You are trying to show the outcomes of spinning a spinner on one side of an area model. The spinner is broken into 3 equal pieces. How would you split up that one side of the area model?
Into 3 equal sections, labeling one section for each of the spinners sections.
3/5 of students in a class got below an 85% on the last test. Using that information, how many students in the whole 8th grade, which has 60 students, would have gotten below an 85%?
3/5
5 x 12 = 60
So, 36/60
You have 2 bags of cubes. Each bag has 1 red, 1 yellow, and 1 blue block in them. What are all the possible outcomes when drawing 1 cube from each bag?
R/Y, R/R, R/B, Y/R, Y/Y, Y/B, B/R, B/Y, B/B
A bag contains one green marble, two yellow marbles, four blue marbles, and five red marbles.
If you triple the number of green, yellow, blue, and red marbles in the bag, what will be the theoretical probability of drawing a blue marble?
12/36
4 x 3= 12
12 x 3= 36
The chance of a snow day tomorrow is 86%. What is that as a fraction? Simplify if possible.
86/100 or 43/50
You are trying to show the outcomes of spinning a spinner on one side of an area model. The spinner is 1/2 red, 1/3 yellow, and 1/6 blue. How would you split up that one side of the area model?
It would need to be broken into 6 pieces. 3 labeled red, 2 labeled yellow, and 1 labeled blue.
To pay you for mowing the lawn, your grandmother puts money in a bag. The bag has one $10 bill and four $1 bills. You get to draw out two bills.
What is the theoretical probability of getting $11?
8/20 or 2/5
Let’s Make a Meal is a restaurant that lets customers design their own meals. Customers choose items from two categories: one entree and one drink.
How many different meals can be designed?
8 meals
A bag contains one green marble, two yellow marbles, four blue marbles, and five red marbles.
If the probability is multiplied by 3, are all the answers still the same?
Yes, because when simplified the probabilities would be back to the original ones.
A gumball machine contains orange, yellow, and purple gumballs. The probability of getting an orange gumball is 3/4. The probability of getting a yellow gumball is 1/6.
What is the probability of getting a purple gumball?
1/12
Use the picture of the spinner to answer.
Are the possible outcomes 1, 2, and 3 equally likely? Explain.
No, 2 has more area than any of the other numbers. 1 has the least amount of space.
To pay you for mowing the lawn, your grandmother puts money in a bag. The bag has one $10 bill and four $1 bills. You get to draw out two bills.
What is the probability of getting $2? Explain.
12/20
If 8 would be $11, the other 12 would be $2
Let’s Make a Meal is a restaurant that lets customers design their own meals. Customers choose items from two categories: one entree and one drink.
If meals are made randomly, what is the theoretical probability that a meal will include a hamburger?
2/8 or 1/4
A bag contains one green marble, two yellow marbles, four blue marbles, and five red marbles.
How many blue marbles would you need to add to the original bag of marbles to make the probability of drawing a blue marble 1/2?
5+2+1= 8
We already have 4 blue, and 4 + 4= 8
So we need to add 4.
A gumball machine contains orange, yellow, and purple gumballs. The probability of getting an orange gumball is 3/4. The probability of getting a yellow gumball is 1/6.
If there are 36 gumballs in the machine, how many are purple? Yellow? Orange?
P= 1/12= 3/36
Y= 1/6= 2/12= 6/36
O=3/4= 9/12= 27/36
Use the picture of the spinner to answer.
If you spin the spinner 120 times, how many times would you expect to land on 2?
5/12= 50/120
To pay you for mowing the lawn, your grandmother puts money in a bag. The bag has one $10 bill and four $1 bills. You get to draw out two bills.
Would you rather that your grandmother give you $6 per job or use the bills in the bag? Explain.
I would rather get $6 per job, as 12/20 jobs would be $2.
**Answers excepted based upon teacher approval**
Let’s Make a Meal is a restaurant that lets customers design their own meals. Customers choose items from two categories: one entree and one drink.
If meals are made randomly, what is the theoretical probability of a meal having chicken and juice?
1/8