WorksheetsProbability I
Total questions: 14
Worksheet time: 14mins
What is sample space?
a process with an uncertain result
a possible result of an action
a list of all possible outcomes of an event
a single outcome or group of outcomes
A box contains 6 blue pens, 3 black pens and a number of red pens. A pen is chosen at random from the box. The probability of choosing a blue pen is 1/5 . Find the probability of choosing a red pen.
3/10
2/5
3/5
7/10
1/3
1/5
2/5
3/5
A number is chosen at random from the set {x: 1 ≤ x ≤ 100}. Find the probability of choosing a perfect square.
1/20
1/10
1/5
1/4
There are 12 white marbles and a number of black marbles in a bag. A marble is picked at random from the bag. The probability of picking a black marble is 3/7. How many black marbles are there in the bag?
6
7
8
9
In a group of 72 participants, 54 of them are males. then 18 female participants join the group. If a participant is selected at random from the group, find the probability of selecting a female participant.
1/5
2/5
1/2
3/5
A bag contains a total of 320 red beads, blue beads and green beads. 80 of the beads are red. If a bead is selected at random from the bag, the probability of selecting a blue bead is 1/8. Find the number of green beads in the bag.
30
120
200
210
Alice has 11 black buttons, 9 white buttons and some brown buttons. If a button is chosen at random, the probability of choosing a brown button is 2/7 How many black buttons does she need to buy so that the probability of choosing a black button becomes 0.75?
40
44
48
84
3/25
4/25
9/25
2/5
There are 20 blue and red marbles in a bag. Chris picks a marble at random from the bag. Which of the following cannot be the probability of picking a blue marble?
0.4
2/5
5/2
20%
A letter is selected at random from the word ‘PERAK’. Which of the following outcomes is not possible?
A vowel is selected
A consonant is selected
Letter L is selected
Letter K is selected
