Hypothesis testing on either a Texas TI-83 plus or a Sharp EL-9900Watch
I think I need to select "Z-Test" and choose "Stats" on the first option that comes up, but I don't know what I should do from there.
An example of a hypothesis testing question I could get is:
A manufacturer of coloured drawing pins introduces a purple pin that is to make up 15% of the total production. The pins are sold in boxes of 20. A teacher buys a box of pins and discovers that it contains only 1 purple pin. Test, at the 5% significance level, whether or not there is evidence that the probability of a pin chosen at random being purple is less that 0.15.
So what I would do if I was working this out by hand is say:
Therefore insufficient evidence to reject
Does anyone know how to check this on a calculator?
The best way of checking your answer is to use binomial tables, failing that, calculate the sum of the probability of the random variable having every value defined in the range and taking its sum, but this takes far too long to consider doing in an exam. Just stick with the tables.