Mathematics Class 9 probability & statistics

Question 1

If the probability of an event to happen is 0.3 and the probability of the event not happening is:

Accepted Answer

0.7

Question 2

In a frequency distribution, the mid value of a class is 10 and the width of the class is 6. The lower limit is

Accepted Answer

7

Question 3

The range of the data 25,23,24,21,19,32,21,14,13,6,15,11 is

Accepted Answer

26

Question 4

The class mark of the class 90 - 120 is

Accepted Answer

105

Question 5

The sum of all probabilities equal to:

Accepted Answer

1

Question 6

Let m be the mid point and l be the upper class limit of a class in a frequency distribution. The lower class limit is

Accepted Answer

2m-l

Question 7

The probability of drawing an ace card from a deck of cards is:

Accepted Answer

1/13

Question 8

If P(E) = 0.44, then P(not E) will be:

Accepted Answer

0.56

Question 9

The probability of each event, when a coin is tossed for 1000 times with frequencies: Head:455 & Tail: 545 is

Accepted Answer

0.455 & 0.545

Question 10

If P(E) = 0.38, then probability of event E, not occurring is:

Accepted Answer

0.62

Questions 10