Card 1 - Easy

Card 4 – Medium

Card 12 – Medium

A class is going to play three games. In each game some cards are put into a bag. Each card has a square or a circle on it. One card will be taken out, then put back. If it is a circle, the girls score a point. If it is a square, the boys score a point.

a.  Which game are the girls most likely to win? Why?

b.  Which game is it equally likely that the boys or girls win? Why?

c.  Are any of the games unfair? Why?

Card 3 – Easy

Card 2 – Hard

Card 5 – Medium

Card 6 – Medium

Les, Tom, Nia and Ann are in a singing competition.

To decide the order in which they will sing all four names are put into a bag.

Each name is taken out of the bag, one at a time, without looking.

(a) Write down all the possible orders with Tom singing second.

(b) In a different competition there are 8 singers.

The probability that Tom sings second is .

Work out the probability that Tom does not sing second.

Card 11 – Easy

There are ten coloured counters in a bag. Three are blue, five are red and the rest are yellow.
A counter is pulled out at random. Calculate the probability of the counter being:

a.  blue b. red c. yellow

Card 7 – Hard

There are some cubes in a bag. The cubes are either red (R) or black (B).

If you take a cube at random out of the bag, the probability that it will be red is

The teacher says:

(a) What is the probability that the cube will be black?

(b) A pupil takes one cube out of the bag. It is red.
What is the smallest number of black cubes there could be in the bag?

(c) Then the pupil takes another cube out of the bag. It is also red.
From this new information, what is the smallest number of black cubes there could be in the bag?

Card 8 – Easy

Counters are placed in a box. For each of the following boxes, find:

a.  The probability of a shaded counter being drawn out at random;

b.  The probability of a ‘not shaded’ counter being drawn out

Card 9 – Medium

A card is chosen at random from a deck of 52 playing cards.
Calculate the probability that it is:

a.  A black card b. An ace c. A diamond

d.  Not a picture card e. Not a king f. The ace of spades.

Card 10 – Easy

Write down an event for which the outcome is:

a.  Certain b. Impossible c. Very likely

d.  Unlikely e. Even chance