### NRICH DOG ATE HOMEWORK

These are just a sample of the questions that might be asked. All of this is by way of saying that it is vital that students – all students, not just the higher achieving groups who will do higher level exams – need to be helped to understand conditional probability. Register for our mailing list. What figure should go in the denominator here? If that’s how it’s taught, then yes, it is dry, apparently pointless, and difficult to justify spending time and effort on.

Can we simplify that? Rather than drawing attention to this, give students a chance to observe that the game “isn’t fair”, and use this to discuss that perhaps Team Yeti are a much stronger team Register for our mailing list. Given that an athlete is taking the banned substance, what is the probability that the test is negative? Is the proportion of games won by the Yetis Beavers the same as the probability that they will score a goal?

This problem is part of the Great Expectations: Considering just the drawswho scored first most often? The same problem can be nric in this way: That wouldn’t matter if it were purely a mathematical problem, but failing to understand information given in this way is at the root of many medical and legal miscalculations. A homeaork experiment which will introduce students to tree diagrams, and help them to understand that outcomes may not be equally likely.

# Great Expectations :

Which Zte Will Win? If she has breast cancer, the probability that she tests positive on a screening mammogram is 90 percent. It is designed for classroom use; see the Teachers’ Resources for a suggested classroom approach. A practical experiment which uses tree diagrams to help students understand the nature of questions in conditional probability.

Start with questions about the actual results. How many of those who test positive actually have breast cancer? In each question, the numerator is therefore 3. Who is likely to score more often?

All of this is by way of saying that it is vital that students – all students, eog just the higher achieving groups who will do higher level exams – need to nricy helped to understand conditional probability.

Age 11 to 14 Challenge Level: A certain teacher, Mr L I Detector, claims he can tell when students are lying about their homework. Given that an athlete is not taking the banned substance, what is the probability that they test positive? There are more resources, plus video clips from an expert, in the Maths and Our Health pack – The test is positive: A practical experiment provides data.

How likely are you to be chosen? The articles Probability through Problems outline the thinking behind the approach, and the resources can form the basis of an entire secondary school probability curriculum. If that’s how it’s taught, then yes, it is dry, apparently pointless, and difficult to justify spending time and effort on. Moving onto expected results provides a context to establish the multiplication rule in probability, and an intuitive approach to conditional probability.

## Which Team Will Win?

But what are the odds it’s wrong? Can we simplify that? What’s the fairest way to choose 2 from 8 potential prize winners?

The denominator in each case is different, however, since we are considering these 3 athletes as a proportion of a different set of athletes in each case. hokework

How would this change the expected results? To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice. Are any of the results in the tally interesting or surprising? It is best to avoid asking students what they ats to happen at this stage so that guessing is not encouraged, but if they do have ideas about what they might expect, they should be written up on the board, to be considered further when more data is available.

Register for our mailing list. Frankly, who cares what the chance is of getting a blue ball, given that the previous one was red. To support this aim, members of the NRICH team dogg in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

Display this on the first set of branches of the second tree diagram.