Probability

500 people took a driving test. 62% passed first time. Of those who failed first time, 50% passed second time. How many people passed on their second attempt?

The probability that a biased coin lands on heads is 0.42. The coin is thrown 150 times. Work out the expected number of heads.

A spinner is spun 400 times and lands on red 86 times. (a) Work out the relative frequency of red. (b) Estimate how many times it will land on red in 1000 spins. (c) Explain whether the spinner is likely to be fair if it has 4 equal sections.

In a class of 50 students, 28 study French, 20 study Spanish and 9 study both. (a) Draw/describe a Venn diagram. (b) A student who studies French is chosen at random. Find the probability that they also study Spanish.

A bag contains 8 red and 2 blue counters. Two counters are taken at random without replacement. Work out the probability that they are the same colour.

The probability that a biased coin lands on heads is 0.24. The coin is thrown 250 times. Work out the expected number of heads.

A bag contains 9 red and 3 blue counters. Two counters are taken at random without replacement. Work out the probability that they are the same colour.

250 people took a driving test. 48% passed first time. Of those who failed first time, 60% passed second time. How many people passed on their second attempt?

The probability that a biased coin lands on heads is 0.3. The coin is thrown 220 times. Work out the expected number of heads.

In a survey of 80 people: 30 are under 30. Of these, 18 use social media daily. Of the people aged 30 or over, 20 use social media daily. (a) Complete a two-way table. (b) A daily user is chosen at random. Find the probability they are under 30.