Open In App

Probability Class 10 Important Questions

Last Updated : 11 Jul, 2025
Summarize
Comments
Improve
Suggest changes
Share
Like Article
Like
Report

Probability is a fundamental concept in mathematics for measuring of chances of an event happening By assigning numerical values to the chances of different outcomes, probability allows us to model, analyze, and predict complex systems and processes.

Probability Formulas for Class 10

It says the possibility of an event happening is equal to the ratio of the number of favorable outcomes and the total number of outcomes.

  • Probability of event to happen P(E) = Number of favourable outcomes/Total Number of outcomes
  • For any event E: P (E) + P ( \bar{E}) = 1,
    where E stands for ‘not E’
  • P ( \bar{E}) = 1 - P(E)

Probability Class 10 Important Questions: Solved

Question 1: You toss two coins at the same time. What is the probability of getting at least one head?

Solution:

The possible outcomes when tossing two coins are: HH, HT, TH, TT (where H = Head, T = Tail).

Total possible outcomes = 4.
The favorable outcomes for "at least one head" are: HH, HT, TH (3 outcomes).

P(at least one head) = number of outcomes with one head / total number of outcomes.
P(at least one head) = 3/4​

Question 2: Two dice are rolled together. What is the probability of getting a sum of 7?

Solution:

The possible outcomes when rolling two dice = 6×6=36.

The favorable outcomes where the sum is 7: (1,6), (2,5), (3,4), (4,3), (5,2), (6,1) (6 outcomes).

P(sum of 7) = number of outcomes with sum of 7/ total number of outcomes.
P(sum of 7) = 6/36 = 1/6

Question 3: A box contains 12 balls out of which x are black. If one ball is drawn at random from the box, what is the probability that it will be a black ball? If 6 more black balls are put in the box, the probability of drawing a black ball is now double of what it was before. Find x.

Solution :

Total number of balls = 12
Number of black Balls = x.

P(Getting a black ball ) = number of black Balls / total number of balls.
P(Getting a black ball ) = x/12

After adding 6 more black balls

Total number of balls = 18
Number of black Balls = x + 6.

Pnew (getting black balls) = x + 6/18
Now, Pnew = 2 × POld

(x + 6)/18 = 2 × (x/12)
(x + 6)/18 = 2x/12
Simplifying the above equation
x = 3

Question 4: If the probability of winning a game is 0.6, what is the probability of loosing it.

Solution:

Given the probability of winning the game is 0.6 ⇒ P(E) = 0.6

As we know, P (E) + P ( \bar{E}) = 1

then probability of loosing the game P ( \bar{E}

P ( \bar{E} = 1 - P(E)
P(Loosing the game) = 1 - 0.6 = 0.4
P(Loosing the game) = 0.4

Also Read:

Probability Class 10 Important Questions : Unsolved


Class 10 : Probability Worksheet with Answers - Free PDF Download


Next Article
Article Tags :

Similar Reads