Introduction Quiz - CBSE Class 7 Mathematics
Free practice quiz: Introduction (CBSE Class 7 Mathematics). 11 multiple-choice questions with answers and explanations. Play online, no sign-up needed.
This CBSE Class 7 Mathematics practice quiz has 11 multiple-choice questions on Introduction, and 11 of them come with an explanation. Try the 5 sample questions below (tap an option to check yourself), then play the full quiz online. No sign-up needed.
Start quiz: 11 questions, freeLearn the key ideas Beta
Experiments, Outcomes and Events
- An experiment is an action like tossing, rolling or picking, whose result we cannot know in advance.
- Each possible result is an outcome. An event is the group of outcomes we are interested in.
- Outcomes are equally likely when each one has the same chance, like a fair coin or well-shuffled cards.
Common mistake: Counting only some outcomes as total, like forgetting the other colours in a bag or other groups in a class.
Probability Formula
- Probability tells how likely an event is, using equally likely outcomes.
- Divide favourable outcomes by total outcomes, then simplify the fraction to lowest terms.
Common mistake: Writing favourable over unfavourable, like a over b, instead of a over the total a + b.
Range of Probability
- Probability is always between 0 and 1, including both.
- An impossible event has probability 0; a certain event has probability 1.
- Chances of an event happening and not happening always add up to 1.
Common mistake: Giving an answer bigger than 1, which happens when numerator and denominator are swapped.
Two Experiments Together
- When two things happen together, like rolling two dice, list outcomes as pairs.
- Total pairs equal outcomes of the first experiment times outcomes of the second.
Common mistake: Adding outcomes, m + n, instead of multiplying them, m × n, when two experiments happen together.
Exam tips
- First write the total number of outcomes, then count the favourable ones carefully.
- Recall what a standard deck contains: its suits, cards per suit, and face cards.
- Always simplify your fraction and check the answer lies between 0 and 1.
Beta: made with AI and checked by a second AI. A teacher has not reviewed it yet.
Sample questions
What is the probability of flipping a coin and it landing on heads?
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Answer: A. 1/2
A fair coin has two sides, heads and tails, so the probability of flipping heads is 1 out of 2 outcomes.
There are 3 red marbles and 2 blue marbles in a bag. What is the probability of drawing a red marble?
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Answer: A. 3/5
There are 3 red marbles out of a total of 5 marbles, so the probability is 3/5.
If you have 4 different books, what is the probability of picking a specific book at random?
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Answer: A. 1/4
There is 1 specific book out of 4, so the probability is 1/4.
If there are 10 boys and 15 girls in a class, what is the probability of picking a boy?
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Answer: A. 2/5
There are 10 boys out of a total of 25 students, so the probability is 10/25 or 2/5.
In a jar with 7 red balls and 3 green balls, what is the probability of picking a green ball?
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Answer: A. 3/10
There are 3 green balls out of a total of 10, so the probability is 3/10.
More questions in this quiz
Answers and explanations are in the full quiz.
- If you roll a six-sided die, what is the probability of rolling a 4?
- What is the probability of choosing a vowel from the English alphabet?
- A deck of cards has 52 cards. What is the probability of drawing a spade?
- What is the probability of drawing a queen from a standard deck of cards?
- If you roll 2 dice, what is the probability of getting a double six?
- What's the probability of drawing an Ace from a shuffled deck of cards?
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