Probability Trees
A bag contains only red and blue tokens. The probability of selecting a red token is 3/10. What is the probability of selecting a blue token?
7/10
If I toss a coin 8 times, how many tails should I expect?
4 tails.
How many outcomes must be possible in a binomial distribution?
2
What value defines the centre of a normal distribution curve?
The mean.
What is the sum of the internal angles of a triangle?
180o
A bag contains only red and blue tokens. The probability of selecting a red token is 3/10. A token is selected and replaced. What is the probability of selecting two red tokens in a row?
9/100
What is a fair game?
When E(X)=0.
Suppose X ~ B(10, 0.4). How many trials were conducted?
10
What does standard deviation measure?
The spread of data (from the mean).
A cube has the side length 5cm. What is the volume?
125cm3
A bag contains only red and blue tokens. The probability of selecting a red token is 3/10. A token is taken and not replaced. What is the probability of selecting a two red tokens in a row?
1/15
When going on a fishing trip, Paul has a 23% chance to catch 0 fish, 31% chance to catch 1 fish, 27% chance to catch 2 fish and a 19% chance to catch 3. How many fish should he expect to catch on his next trip?
1.42 fish
Suppose X ~ B(10, 0.4). What is the variance?
2.4
The amount of juice from a batch of oranges is normally distributed with a mean of 35mL and a standard deviation of 5mL. What percentage of oranges will produce between 25mL and 35mL of juice?
47.7%
A right angled triangle has two shorter sides of length 3cm and 4cm. What is the length of the hypotenuese?
5cm
A bag contains only red and blue tokens. The probability of selecting a red token is 3/10. A token is selected and not replaced. What is the probability of selecting at least one red token from two picks.
8/15
A spinner is numbered from 1 to 4 and the player wins the amount of dollars the spinner lands on. If the game costs $2 to play, calculate the expected return.
+$0.50
Suppose X ~ B(10, 0.4). Find the P(X=3)
0.215
The amount of juice from a batch of oranges is normally distributed with a mean of 35mL and a standard deviation of 5mL. What is the probability a randomly selected orange will produce at least 28mL of juice.
0.919 / 91.9%
In a right angled triangle, you are given the length of the hypotenuse and the side adjacent to a known angle. Which trigonometric ratio do you need to use?
Cosine
A bag contains only red and blue tokens. The probability of selecting a red token is p. A token is selected and replaced. Write an expression for the probability of selecting two different coloured tokens.
2p - 2p2 or 2p(1-p)
A spinner is numbered from 1 to 8 and the player wins the double the amount of dollars the spinner lands on. How much should the casino charge to make $1 per game?
$10
Suppose X ~ B(10, 0.4). Find P(X≥4).
0.618
The amount of juice from a batch of oranges is normally distributed with a mean of 35mL and a standard deviation of 5mL. Gary only selects the top 10% juiciest oranges. What is the minimum mL of one of Gary's oranges?
41.4mL
A sector has a radius of 5cm and and angle of 35o. Calculate the area. Give your answer to 3 s.f.
7.64cm2