Using probability to estimate
It's really useful to be able to predict the future! We can use probability calculations to estimate or predict what we think may happen in a given situation.
In GCSE maths, these are usually pretty simple situations involving probability experiments. For example, the chance of rolling a two on a fair six-sided die is 1/6.
If I roll the die 300 times, I would expect 1/6 of those rolls to result in a two. 1/6 of 300 is 50, so I would expect to see 50 twos in 300 rolls.
To calculate an estimate, all you need to do is multiply the probability of that event happening by the number of tries. This is really easy with a calculator, but you should make sure you are confident with calculating fractions of amounts and multiplying by decimals for non-calculator questions.
Find the number of red counters in a bag given the number of counters in total and probability of picking one red counter (question starts about halfway in).