1. 
The table below shows the number of male and female that play a
sport in an
IB class 


Male 
Female 
Total 
Sport 
04 
08 
12 
No Sport 
14 
24 
38 
Total 
18 
32 
50 


Calculate, on
randomly selecting a student, the probability of selecting: 

(i) 
A
female?


(ii) 
A
male sports player?


(iii) 
A
sports player given she is female? (this is a conditional probability
question) We are only interested in females =


(iv) 
Male given he is a sports player? (this is a conditional probability
question) We are only interested in the sports players =




2. 
A
bowl of fruit contained 5 oranges and 7 apples a child selected
two pieces of fruit to take to school. 

(i) 
Draw a tree diagram to show the possible choices made 

(ii) 
Calculate the
probability of selecting an orange? 

(iii) 
Given an orange was
selected, what is the probability that a apple was selected first? 




(i) 





(ii) 
There are three ways of getting an orange 







(iii) 
We now need to use
the conditional probability formula 











