| 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 =
 |
| |
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|
| 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? |
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|
| |
(i) |
|
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| |
(ii) |
There are three ways of getting an orange |
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| |
(iii) |
We now need to use
the conditional probability formula |
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