These coins are tossed simultaneously 200 times with the followi

Previous Year Papers

Download Solved Question Papers Free for Offline Practice and view Solutions Online.

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.
Advertisement

 Multiple Choice QuestionsShort Answer Type

31.

On one page of a telephone directory, there were 200 telephone numbers. The frequency distribution of their unit place digit (for example, in the number 25828573, the unit place digit is 3) is given in the table below:

Table

Digit

0

1

2

3

4

5

6

7

8

9

Frequency

22

26

22

22

20

10

14

28

16

20

 
 

Without looking at the page, the pencil is placed on one of these numbers, i.e., the number is chosen at random. What is the probability that the digit in its unit place is 6?

181 Views

32.

The record of a weather station shows that out of the past 250 consecutive days, its weather forecasts were correct 175 times:

(i)  What is the probability that on a given day it was correct?
(ii)  What is the probability that it was not correct on a given day? 

166 Views

33.

A tyre manufacturing company kept a record of the distance covered before a tyre needed to be replaced. The table shows the results of 1000 cases.  [CBSE 2012 (March)]

Table

Distance (in km)

less than 400

400 to 900

900 to 1400

more than 1400

Frequency

210

325

385

80

If you buy a tyre of this company, what is the probability that:

(i) it will need to be replaced before it has covered 400 km?
(ii)  it will last more than 900 km?
(iii)  it will need to be replaced after it has covered somewhere between 400 km andb 1400 km?
(iv)  it will not need to be replaced at all?
(v)  it will need to be replaced?

239 Views

34.

The percentage of marks obtained by a student in the monthly unit tests are given below:
Table

Unit test

I

II

III

IV

V

Percentage of marks obtained

69

71

73

68

74

Based on this data, find the probability that the student gets more than 70% marks in a unit test.

578 Views

Advertisement
35.

An insurance company selected 2000 drivers at random (i.e., without any preference of one driver over another) in a particular city to find a relationship between age and accidents. The data obtained are given in the following table:

Table

Age of drivers

Accidents in one year

(in years)

0

1

2

3

over 3

18–29

440

160

110

61

35

30-50

505

125

60

22

18

Above 50

360

45

35

15

9

Find the probabilities of the following events for a driver chosen at random from the city:

(i) being 18–29 years of age and having exactly 3 accidents in one year.
(ii)  being 30-50 years of age and having one or more accidents in a year.
(iii)  having no accidents in one year.

139 Views

36.

Consider the following frequency distribution table, which gives the weights of 38 students of a class:

(i)  Find the probability that the weight of a student in the class lies in the interval 46-50 kg.

(ii)  Give two events in this context, one having probability 0 and the other having probability 1:

Table

Weights (in kg)

Number of students

31-35

9

36-40

5

41–45

14

46-50

3

51-55

1

56-60

2

61-65

2

66-70

1

71–75

1

Total

38

594 Views

37.

Fifty seeds were selected at random from each of 5 bags of seeds, and were kept under standardised conditions favourable to germination. After 20 days the number of seeds which had germinated in each collection were counted and recorded as follows:

Table

Bag

1

2

3

4

5

Number of seeds germinated

40

48

42

39

41

What is the probability of germination of
(i)   more than 40 seeds in a bag?
(ii)  49 seeds in a bag?
(iii)  more than 35 seeds in a bag?

452 Views

38.

Two coins are tossed simultaneously 1000 times with the following frequencies of different outcomes.

Outcome

Frequency

2 heads

350

1 head

310

No head

340

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

(i)  at least 1 head
(ii)  at most 1 head

412 Views

Advertisement
39.

Two coins are tossed simultaneously 500 times,

and we get

Result

2 head

1 head

No head

Frequency

105

275

120

Find the probability of occurrence of

(i)  two heads
(ii)  all tails.

215 Views

Advertisement

40.

These coins are tossed simultaneously 200 times with the following frequencies of different outcomes:

Outcome

Frequency

3 heads

24

2 heads

70

1 head

75

3 tails

31

Compute the probability of getting

(i)  less than 2 heads
(ii)  3 heads.


Solution not provided.

Ans.   left parenthesis straight i right parenthesis space 53 over 100 space space space space left parenthesis ii right parenthesis space 3 over 25

141 Views

Advertisement
Advertisement