Exercise 3c
1 Two coins are tossed. What is the probability that both show heads?
2 Two dice are tossed. Find the probability of getting a double six.
3 Jack has two tubes of sweets. Each tube contains 10 red sweets
and 30 sweets of other colours. Jack takes one sweet, chosen at
random, from each tube. Find the probability that
a he takes a red sweet from a tube
b he takes a sweet that is not red from a tube
e both the sweets he takes are not red.
4 The probability that Lauren will win the girls' 100 m race is
and the probability that Liam will win the boys' 100 m race is
What is the probability that
5′
a both of them will win their events
b neither of them will win their event?
5 A mother has an equal chance of giving birth to a boy or a girl. Holly
plans to have two children.
a What is the probability that the first is a girl?
b What is the probability that both are boys?
e What is the probability that neither is a boy?
6 The probability that Olivia will have to wait before she can cross
Westgate Street is and the probability that she will be able to
cross High Street without waiting is.
What is the probability that
a she does not have to wait to cross Westgate Street
b
she has to wait to cross High Street
e
she can cross both streets without waiting?