## Grade 11 Math SL SECTION A – Practice questions on Tree diagram – 06/10/2014

**PROBABILITY**

**SOLVE THE FOLLOWING QUESTIONS USING TREE DIAGRAMS :Ãƒâ€šÃ‚Â **

1. Stephano is having problems. His desktop computer will only boot up 90% of the time and his laptopÃƒâ€šÃ‚Â will only boot up 70% of the time.

(a) Draw a tree diagram to illustrate this situation.

(b) Use the tree diagram to determine the chance that:

(i) both will boot up Ãƒâ€šÃ‚Â (ii) Stephano has no choice but to use his desktop computer.

2.Ãƒâ€šÃ‚Â Bag A contains 4 red jelly beans and 1 yellow jelly bean. Bag B contains 2 redÃƒâ€šÃ‚Â and 3 yellow jelly beans. A bag is randomly selected by tossing a coin, and oneÃƒâ€šÃ‚Â jelly bean is removed from it. Determine the probability that it is yellow.

3.Ãƒâ€šÃ‚Â Machine A cans 60% of the fruit at a factory. Machine B cans the rest. Machine A spoils 3% ofÃƒâ€šÃ‚Â its product, while Machine B spoils 4%. Determine the probability that the next can inspected at thisÃƒâ€šÃ‚Â factory will be spoiled.

4.Ãƒâ€šÃ‚Â A bin contains 4 blue and 5 green marbles. A marble is selected from this bin and its colour is noted.Ãƒâ€šÃ‚Â It is then replaced. A second marble is then drawn and its colour is noted. Determine the probabilityÃƒâ€šÃ‚Â that:

(a)Ãƒâ€šÃ‚Â both are blue Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â (b) the first is blue and the second is green Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â (c) there is one of each colour.

5.Ãƒâ€šÃ‚Â Sylke has bad luck with the weather when she takes her summer holidays.Ãƒâ€šÃ‚Â She estimates that it rains 60% of the time and it is cold 70% of the time.

(a) Draw a tree diagram to illustrate this situation.

(b) Use the tree diagram to determine the chance that for SylkeÃƒÂ¢Ã¢â€šÂ¬Ã¢â€žÂ¢s holidays:

(i) it is cold and raining Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â Ãƒâ€šÃ‚Â (ii) it is fine and cold.

**Duration : 45 minutesÃƒâ€šÃ‚Â **

**Submission Date : 8th October,2014**

Regards,

Krishna