A vegetable basket contains 12 peppers, of which 3 are red, 4 are green and 5 are yellow. Three peppers are taken, at random and without replacement, from the basket.
The probability that Henk goes swimming on any day is 0.2. On a day when he goes swimming, the probability that Henk has burgers for supper is 0.75. On a day when he does not go swimming, the probability that he has burgers for supper is x. This information is shown on the following tree diagram.
The probability that Henk has burgers for supper on any day is 0.5.
(i) Find x.
(ii) Given that Henk has burgers for supper, find the probability that he went swimming that day.
Boxes of sweets contain toffees and chocolates. Box A contains 6 toffees and 4 chocolates, box B contains 5 toffees and 3 chocolates, and box C contains 3 toffees and 7 chocolates. One of the boxes is chosen at random and two sweets are taken out, one after the other, and eaten.
(i) Find the probability that they are both toffees.
(ii) Given that they are both toffees, find the probability that they both came from box A.
A box contains five balls numbered 1, 2, 3, 4, 5. Three balls are drawn randomly at the same time from the box.
(i) By listing all possible outcomes (123, 124, etc.), find the probability that the sum of the three numbers drawn is an odd number.
The random variable \(L\) denotes the largest of the three numbers drawn.
(ii) Find the probability that \(L\) is 4.
A box contains 10 pens of which 3 are new. A random sample of two pens is taken.
Show that the probability of getting exactly one new pen in the sample is \(\frac{7}{15}\).