1. Experiment Explain whether or not each of these statements is right.
[ S3.2 Core Starter]
Explain whether or not each of these statements is right.
I’ve spun an unbiased coin three times and got three heads. It is more likely to be tails than heads if I spin it again.
There are three red beads and five green beads in a bag. I pick a bead at random. The probability that it is red is 3/5.
I have thrown an unbiased dice 10 times and not yet got a six. The probability of getting a six on my next throw is more than 1/6.
Janet buys two raffle tickets. If she chooses two tickets from different places in the book she is more likely to win than if she chooses two consecutive tickets.
Preamble
This straightforward activity is designed to give pupils the opportunity to talk about the underlying ideas behind simple probability. The ensuing discussion is important.
Possible content
Elementary probability based on equally likely outcomes.
Resources
None.
Solution/Notes
All are false but as ever the explanation as to why is crucial.
Each spin of the coin is independent of past or future spins so the probability will remain 1/2.
The probability of red will be the number of reds divided by the total possibilities. So the probability should be 3/8.
The same logic as a) applies. Hence the probability of a six remains 1/6.
Again, the logic remains the same as for a) and c).
Original Material © Cambridge University Press 2010
Original Material © Cambridge University Press 2010