Probability：练习题

A fair six-sided die is rolled once. What is the probability of rolling a number greater than 4?

A spinner is divided into five equal sections colored Red, Blue, Green, Yellow, and Orange. If the spinner is spun 200 times, calculate the expected frequency of the spinner landing on 'Red'.

A bag contains 4 red counters, 3 blue counters, and 3 yellow counters. One counter is taken at random from the bag. What is the probability that the counter is NOT blue?

Two fair coins are tossed at the same time. What is the probability of obtaining at least one Head?

The probability that it will rain tomorrow is 0.15. What is the probability that it will NOT rain tomorrow?

A fair six-sided die is rolled once. Find the probability that the number landed on is a prime number.

The probability of a seed germinating is \(0.85\). If a gardener plants \(400\) seeds, calculate the expected frequency of seeds that will germinate.

A box contains 3 red marbles and 7 blue marbles. Two marbles are taken at random without replacement. Calculate the probability that both marbles are red.

A fair six-sided die is rolled once.
(a) Write down the probability that the die lands on a number greater than 4.
(b) The die is rolled 150 times. Work out an estimate for the number of times the die will land on a number greater than 4.

A bag contains 10 discs. 7 of the discs are blue and 3 of the discs are red.
Two discs are taken at random from the bag without replacement.
(a) Complete the probability tree diagram to show all possible outcomes.
(b) Calculate the probability that both discs taken are red.
(c) Calculate the probability that at least one of the discs taken is blue.