Mean

Q.

The mean of the following distribution is:

$$\begin{array}{ccccc}{x}_i& 10& 13& 16& 19\\ f_i& 2& 5& 7& 6\end{array}$$

1. 15.35

2. 15.2

3. 16

4. 15.55

Q.

Virender Sehwag’s score card for a five match ODI series is 23, 89, 76, 54, 102 runs respectively. What is Sehwag’s mean score for the tournament?

1. 66.8

2. 67.8

3. 68.8

4. 65.8

Q.

What is meant by the mean of a given set of observations?

1. The most frequently occuring value of the observation.

2. The average value of the given set of observations

3. The value of a given number of observations which divides it into exactly two parts.

4. All of these

Q. If the mean of 100 observations is 50, then the sum of all the observations is ____.

1. 5105
2. 5260
3. 5000
4. 5050

Q.

The following table shows the marks obtained by 5 students in a class. What is the average marks of the class?

$$\begin{array}{cc}\text{Marks}& \text{Frequency}\\ 98& 1\\ 65& 1\\ 88& 2\\ 54& 1\end{array}$$

1. 76.6

2. 77.6

3. 78.6

4. 78.9

Q. Rohit scored 92, 85, and 78 in three Maths tests. How much should he score in the 4th test so as to get an average of 87 in four Maths test?

1. 92 marks
2. 91 marks
3. 95 marks
4. 93 marks

Q.

The mean of 15 observations is 8. If the mean of the first eight observations is 7 and that of the last eight observations is 10, then the value of the 8th observation is _____.

1. 16

2. 13

3. 15

4. 14

Q. The mean for counting numbers upto 100 is

1. 51.5
2. 50.5
3. 56.5
4. 50

Q.

The following scores were obtained in a statistics exam

$$\begin{array}{cccccc}classinterval& [50,60)& [60,70)& [70,80)& [80,90)& [90,100)\\ Classvalue{x}_i& 55& 65& 75& 85& 95\\ Frequency{f}_i& 1& 4& 6& 5& 2\end{array}$$

i) Considering the class value, the average score of the whole class is_____.

ii) Ratio of the no. of students who scored above 80 to the no. of students who scored below 70 is______.

1. 65.667, 3:4

2. 76.667, 7:5

3. 68.667, 7:3

4. 81.333, 3:5

Q.

The mean of the above frequency distribution is 3.5, then the value of x is:
$\begin{array}{cccccc}Variable& 1& 2& x& 4& 5\\ Frequency& 2& 3& 4& 5& 6\end{array}$

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