Trail

Q. If a coin is tossed twice what is the probability of getting two heads together

Q. Three unbiased coins are tossed. What is the probability of getting (a ) at least two head (b) at most two heads (c)two heads

Q.

A die is thrown once. Find the probability of getting at most 2.

Q.

Three similar coins were tossed simultaneously 500 times and the frequency distribution of heads obtained on each toss is as below.

$$\begin{array}{ccccc}\text{Number of heads}& 0& 1& 2& 3\\ \text{Frequency}& 60& 175& 200& 65\end{array}$$

Find the probability of (i) getting all three heads;

(ii) getting an odd number of heads. [2 MARKS]

Q.

What is the maximum possible value of the probability of an event?

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Q. Arun and Nita are playing badminton.The probability of Arun winning the match is 0.75. Which of the following statements is true regarding the given information?

1. Arun will win the match.
2. Nita will win the match.
3. The chances of Arun winning the match are higher than Nita.
4. The chances of Nita losing the match are lower than Arun.

Q. Question 2 (ii)
Which of the following experiments have equally likely outcomes? Explain.
"A player attempts to shoot a basketball. She/he shoots or misses the shot."

Q. Question 12.
Sushma tosses a coin 3 times and gets tail each time. Do you think that the outcome of next toss will be tail ? Give reasons.

Q.

What is the number of outcomes when a coin is tossed and then a die is rolled only in case a head is shown on the coin?

1. $6$

2. $7$

3. $8$

4. None of these

Q. In a class, there are p girls and q boys. A student is selected at random. then find the
probability of selecting a girl.

Q.

Two coins are tossed simultaneously $1000$ times with the following frequencies at different outcomes

$\begin{array}{cc}\text{Overhead}& \text{Frequency}\\ 2\text{heads}& 350\\ 1\text{head}& 310\\ \text{No head}& 340\end{array}$

if these two coins are tossed again, find the probability of getting

(i) at least 1 head

(ii) at most one head

Q.

An unbiased dice is thrown. What is the probability of getting an even number or a multiple of 3?

1. 

2. 

3. 

4. 

Q.

Define a trial.

Q.

What is the minimum possible value of the probability of an event?

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Q. Three coins are tossed simultaneously 200 times with the following frequencies of different outcomes:

Outcome	3 heads	2 heads	1 head	No head
Frequency	23	72	77	28

Find the probability of getting at most two heads.

Q. Three coins are tossed simultaneously 100 times with the following frequencies of different outcomes:

Outcome:	No head	One head	Two heads	Three heads
Frequency:	14	38	36	12

If the three coins are simultaneously tossed again, compute the probability of:
(i) 2 heads coming up.
(ii) 3 heads coming up.
(iii) at least one head coming up.
(iv) getting more heads than tails.
(v) getting more tails than heads.

Q. Define an elementary event.

Q. Given below is the frequency distribution of wages (in Rs) of 30 workers in a certain factory:

Wages (in Rs)	110-130	130-150	150-170	170-190	190-210	210-230	230-250
No. of workers	3	4	5	6	5	4	3

A worker is selected at random. Find the probability that his wages are:
(i) less than Rs 150
(ii) at least Rs 210
(iii) more than or equal to 150 but less than Rs 210.

Q. A die is rolled twice. Find the probability that 5 will come up both the times.

1. $\frac{1}{36}$
2. $\frac{18}{36}$
3. $\frac{6}{36}$
4. $\frac{4}{36}$

Q.

If the probability of winning a game is 0.9 , then find the probability of losing the game

Q. If a coin is tossed two times, what is the probability of (i) Getting head at least once? (ii) Getting exactly one head?

Q. A die is rolled 10 times and the data is tabulated below:

Number	Frequency
1	2
2	2
3	1
4	3
5	2
6	1

If we want to find the probability of getting an even number, what is the number of trials where the event happened?

1. 2
2. 5
3. 6
4. 4

Q.

What is each iteration of an experiment called?

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Q. A die is thrown 100 times. If the probability of getting an even number is $\frac{2}{5}$. How many times an odd number is obtained?

Q. The table given below shows the marks obtained by 30 students in a test.

Marks (Class interval)	Number of students (Frequency)
1−10	7
11−20	10
21−30	6
31−40	4
41−50	3

One of these students is chosen at random. What is the probability that his marks lie in the interval 21−30?

Q. In a lottery, there are 10 prizes and 20 blanks. What is the probability of getting a prize?

Q. It is given that the probability of winning a game is 0.7. What is the probability of losing the game?
(a) 0.8
(b) 0.3
(c) 0.7
(d) 0.07

Q. There are 50 eggs in a box 20 of them are broken.At random two eggs are taken one by one consecutively without replacement.What is the probability that
(i)both of them are good
(ii)both of them are broken
(iii)one of them is good and the other is broken

Q. The table given below shows the ages of 75 teachers in a school.

Age (in years)	18−29	30−39	40−49	50−59
No. of teachers	5	25	35	10

Here 18−29 means from 18 to 29, including both.
A teacher from the school is chosen at random. What is the probability that the teacher chosen is
(i) 40 or more than 40 years old?
(ii) 49 or less than 49 years old?
(iii) 60 or more than 60 years old?

Q. Which of the following cannot be the probability of an event?

(a) $\frac{1}{3}$

(b) $\frac{3}{5}$

(c) $\frac{5}{3}$

(d) 1