CBSE Class 9 Mental Maths Probability Worksheet

While taking a 5-minute long typing test, Neela typed at a speed of 48 words per minute for the first 3 minutes. What should be her typing speed for the next two minutes if she wants to average 50 words per minute for the whole test?
A. 32 words per minute
B. 52 words per minute
C. 53 words per minute
D. 56 words per minute

Answer : C

Look at the pattern below: 2 + 4 / 2 = 3, 2 + 4 + 6 / 3 = 4, 2 + 4 + 6 + 8 / 4 = 5 According to this, what would be the average of the first twenty even positive integers?
A. 21
B. 20
C. 19
D. 11

Answer : B

Nafisa has a box of bangles. 1/2 of all the bangles in the box are red, 1/3 are green and 1/6 are blue. If Nafisa takes out a bangle from the box without looking, of which colour is it MOST LIKELY to be?
A. Red
B. Green
C. Blue
D. Data  given is not  enough

Answer : B

If two fair coins are tossed simultaneously, what are the chances of both coming up 'Heads'?
A. 10%
B. 25%
C. 50%
D. 75%

Answer : B

Here is a modified dart board. A player scores points by throwing darts at it. Points are earned according to the area of the dart board where the dart lands.
If the dart is thrown twice at this board, which of the following would be the MOST LIKELY total score? (Assume that in both throws the dart lands on the board)

A. 50
B. 75
C. 100
D. 150

Answer : B

Mili and Aastha are playing a game which goes like this: starting with a large pile of matchsticks, each player takes turns to take away 1, 2 or 3 matchsticks from it. No player can pass a turn. The process continues till there are no matchsticks left and the player who takes the last matchstick(s) is the winner.  In a particular game, after a series of moves, 5 matchsticks remain in the pile and it is Mili's turn. What should be the no. of matchsticks she should take to MAKE SURE that she wins the game?

A. 1
B. 2
C. 3
D. It's not possible for her to win this game.  

Answer : A

In a single throw of die , which of the following has more than 50% chance of occurring?
A. getting a non-negative score
B. getting a negative score
C. getting a score of 0
D. getting a score below minus 3

Answer : A

What is the smallest number of colours needed to colour the following figure so that NO TWO regions with more than a point common have the same colour?

A. 2
B. 3
C. 4
D. 5

Answer : A

A fair game is one in which each possible outcome has an equal chance. Two players are playing a game with two dice. Both the dice are rolled simultaneously and the numbers that turn up are added up. If this sum is even, then player 1 gets a point, and if the sum is odd, then player 2 gets a point. Is this a fair game?

A. Yes, the game is fair.
B. No, the game is favourable for player 1.
C. No, the game is favourable for player 2.
D. Can't say.

Answer : A

Of the 15 charts put up in a classroom, 6 are on Science and 8 are made on white chart paper. If 4 of the Science charts are made on coloured chart paper, how many of the charts made on coloured paper are NOT on Science?
A. 1
B. 2
C. 3
D. 4

Answer : C

Question. A coin is tossed once, find the probability of getting 'Head'?
Answer : 1/2

Question. In a pack of 52 cards what is the probability of getting a face card?
Answer : 3/13

Question. A dice is tossed once find the probability of getting a 'prime number'
Answer : 1/2

Question. A dice is tossed once find the probability of getting a number less than 5.
Answer : 2/3

Question. In a pack of 52 cards find the probability of getting two of spades.
Answer : 1/52

Question. In a cricket match, a batsman hits a boundary of 5 times out of 30 balls he plays. Find the probability that he did not hit a boundary.
Answer : 5/6

Question. In a bag there are 5 white, 4 black, 3 red balls. One ball is picked up randomly what is the probability of getting a black ball?
Answer : 1/3

Question. A coin is tossed 500 times with following frequencies :-
Head - 245, Tail - 255. What is the probability of getting head?
Answer : 49/100

Question. In 250 consecutive days weather forecasts were correct 175 times. Find the probability of getting 'not correct' forecast?
Answer : 3/1 0

Question. In class IX total students were 36. Out of which 20 students are boys. Find the probability of girls in the class?
Answer : 4/9

Question. Between 5 and 15 numbers find the probability of having an odd number.
Answer : 4/9

Question. In 1500 families, 814 families have 2 children and rest of families have 1 child. Find the probability of families having 1 child?
Answer : 343/750

Question. In word 'INDIA' what is the probability of getting letter 'I'?
Answer : 2/5

Question. In a bag of 56 apples, 19 were rotten. One apple is chosen at random. Find the probability of getting a fresh apple?
Answer : 37/56

Question. A dice is tossed once, what is the probability of getting number '7'?
Answer : 0

Question. In a bag there are 5 white, 6 black and 3 green cards. One card is drawn at random. What is the probability of having a card which is not green?
Answer : 11/14

Question. In a class of 50 students 70% were passed. What is the probability of a failing child?
Answer : 3/10

Question. In a football team wining possibility is 0.4. What is probability of loosing the game?
Answer : 0.6

Question. In a pack of 52 cards what is the probability of getting a red king?
Answer : 1/26

Question. In a locality there are 67 vehicles. In which 39 are black. What is the probability of a vehicle which is not black?
Answer : 28/67

Question. A survey of 250 students was conducted about the subject 'Statistics'. In which 143 students like statistics. Find the probability of a students who does not like statistics?
Answer : 107/250

Question. In word 'CLASSES'. What is the probability of getting letter 'S'?
Answer : 3/7

Question. In a class of 47 students, 29 students studies Home Science and rest students studies Drawing. Find the probability of Drawing students?
Answer : 18/47

Question. In word 'MATHEMATICS'. What is the probability of a vowel?
Answer : 4/11

Question. Between 1 – 70, what is the probability of numbers which are divisible by '7'?
Answer : 9/68 .