N2014 P2 Q10

N2014 P2 Q10

Junior College 2
10 marks

A game uses the following three sets of \(10\) symbols.

Set 1++++\(\times\)\(\times\)\(\times\)\(\circ\)\(\circ\)*
Set 2+++\(\times\)\(\circ\)\(\circ\)\(\circ\)\(\circ\)**
Set 3++\(\times\)\(\times\)\(\times\)\(\times\)\(\circ\)\(\circ\)\(\circ\)*

One symbol is chosen at random from each set. For example, choosing \(+\) from Set 1, \(\circ\) from Set 2 and \(*\) from Set 3 gives \(+\circ*\).

  1. Find the probability that the three symbols chosen are
    1. three stars,[1]
    2. at least one star,[2]
    3. two crosses and one plus, in any order.[3]
  2. Given that exactly one of the symbols chosen is a star, find the probability that the other two symbols are a plus and a circle.[4]

Solution:

Solution locked

Sign in to view the step-by-step solution

Finding similar questions...
Answer:(i)(a) \(0.002\), (b) \(0.352\), (c) \(0.058\). (ii) \(\frac{71}{306}\approx0.232\).

Need help? Join our JC Math tuition classes.

Learn more