What are equally likely outcomes? Give an example
Outcomes that have the same likelyhood of occurring. Ex: throwing a fair dice
What is the name of this diagram? What does the "+" show?
Sample space diagram. One "+" shows one equally likely outcome.
When do we use a relative frequency and when do we use a sample space diagram?
RF: used when you cannot assume that the outcomes are all equally likely. SSD: when the outcomes are equally likely.
The probability that Mr.Richard will be absent for Science class is 0.0001. Find the probability that he will not be absent.
0.0009
Rosie plants 6 lilies seeds. The table shows the probabilities of plants will grow from 6 seeds. Find the probability that fewer than 4 liles will grow
1 - ( 0.1 + 0.2 + 0.25 ) = 0.45
Two spinners numbered 1 to 4 are thrown. Find the probability of getting a) one 4 and b) at least one 4. (Use a sample space diagram)
a) 1/16 ; b) 7/16
Kane spins 2 coins together. Draw a SSD and explain why Kane is twice as likely to throw 1 Head and 1 Tail as 2 Heads
P ( 1H + 1T) = 2/4 ; P (2H) = 1/4 ; => P(1H+1T) = 2 x P(2H)
An aeroplane is due to depart at 13:00. This table shows the probabilities for its departure time. Find the probability that the departure will be cancelled
100% - 25% - 55% - 10% - 5% = 5%
Lily makes up 2 sets of 3 cards lettered A, B, and C and asked each 2 people to pick from the 2 sets. Find the probability of them picking the same letter (Use SSD)
1/3
Lily chooses a letter from the word: L O V E. Rosie chooses a letter from the word: L O S E. Find the probability of getting the same letters (Use SSD)
3/16
A computer generates 2 random 1-digit-numbers from 0 to 9. Find the probability that the numbers are the same.
10/100 = 1/10
Lily spins a coin and throw a 8 sided dice numbered from 1 to 8. Find the probability of scoring a tail and a prime number.
4/16 = 1/4
6 coins are spun together. There can be up to 6 heads. The table shows the probability of scoring the different numbers of heads. Find the probability of scoring fewer than 4 heads.
1 - 0.02 - 0.09 - 0.23 = 0.66
