Q. Classify the following data as primary or secondary data.

Q. The distance (in km) of 40 engineers from their residence to their place of work were found as follows:
$\begin{array}{cccccccccc}5& 3& 10& 20& 25& 11& 13& 7& 12& 31\\ 19& 10& 12& 17& 18& 11& 32& 17& 16& 2\\ 7& 9& 7& 8& 3& 5& 12& 15& 18& 3\\ 12& 14& 2& 9& 6& 15& 15& 7& 6& 12\end{array}$

Q. The relative humidity (in %) of a certain city for a month of 30 days was as follows:
$\begin{array}{cccccccccc}98.1& 98.6& 99.2& 90.3& 86.5& 95.3& 92.9& 96.3& 94.2& 95.1\\ 89.2& 92.3& 97.1& 93.5& 92.7& 95.1& 97.2& 93.3& 95.2& 97.3\\ 96.2& 92.1& 84.9& 90.2& 95.7& 98.3& 97.3& 96.1& 92.1& 89\end{array}$
(i) Construct a grouped frequency distribution table with classes $84-86,86-88$, etc.
(ii) Which month or season do you think this data is about?
(iii) What is the range of this data?

Q. A study was conducted to find out the concentration of sulphur dioxide in the air in parts per million (ppm) of a certain city. The data obtained for 30 days is as follows:
$\begin{array}{cccccc}0.03& 0.08& 0.08& 0.09& 0.04& 0.17\\ 0.16& 0.05& 0.02& 0.06& 0.18& 0.20\\ 0.11& 0.08& 0.12& 0.13& 0.22& 0.07\\ 0.08& 0.01& 0.10& 0.06& 0.09& 0.18\\ 0.11& 0.07& 0.05& 0.07& 0.01& 0.04\end{array}$

Q. Three coins were tossed 30 times simultaneously. Each time the number of heads occurring was noted down as follows:
$\begin{array}{cccccccccc}0& 1& 2& 2& 1& 2& 3& 1& 3& 0\\ 1& 3& 1& 1& 2& 2& 0& 1& 2& 1\\ 3& 0& 0& 1& 1& 2& 3& 2& 2& 0\end{array}$
Prepare a frequency distribution table for the data given above.

Q.

The blood groups of $30$ students of Class VIII are recorded as follows:
$A,B,O,O,AB,O,A,O,B,A,O,B,A,O,O,$
$A,AB,O,A,A,O,O,AB,B,A,O,B,A,B,O$.
Represent this data in the form of a frequency distribution table. Which is the most common, and which is the rarest, blood group among these students?

Q. A company manufactures car batteries of a particular type. The lives (in years) of 40 such batteries were recorded as follows:
$\begin{array}{cccccccc}2.6& 3.0& 3.7& 3.2& 2.2& 4.1& 3.5& 4.5\\ 3.5& 2.3& 3.2& 3.4& 3.8& 3.2& 4.6& 3.7\\ 2.5& 4.4& 3.4& 3.3& 2.9& 3.0& 4.3& 2.8\\ 3.5& 3.2& 3.9& 3.2& 3.2& 3.1& 3.7& 3.4\\ 4.6& 3.8& 3.2& 2.6& 3.5& 4.2& 2.9& 3.6\end{array}$

Q. The heights of 50 students, measured to the nearest centimetres, have been found to be as follows:
$\begin{array}{cccccccccc}161& 150& 154& 165& 168& 161& 154& 162& 150& 151\\ 162& 164& 171& 165& 158& 154& 156& 172& 160& 170\\ 153& 159& 161& 170& 162& 165& 166& 168& 165& 164\\ 154& 152& 153& 156& 158& 162& 160& 161& 173& 166\\ 161& 159& 162& 167& 168& 159& 158& 153& 154& 159\end{array}$

Q. Thirty children were asked about the number of hours they watched TV programmes in the previous week. The results were found as follows:
$\begin{array}{cccccccccc}1& 6& 2& 3& 5& 12& 5& 8& 4& 8\\ 10& 3& 4& 12& 2& 8& 15& 1& 17& 6\\ 3& 2& 8& 5& 9& 6& 8& 7& 14& 12\end{array}$

Q. The value of $\pi$ upto 50 decimal places is given below:
$3.14159265358979323846264338327950288419716939937510$
(i) Make a frequency distribution of the digits from $0$ to $9$ after the decimal point.
(ii) What are the most and the least frequently occurring digits?

Q. The length of $40$leaves of a plant are measured correct to one millimetre, and the obtained data is represented in the following table:
(i) Draw a histogram to represent the given data. [Hint: First make the class intervals continuous]
(ii) Is there any other suitable graphical representation for the same data?
(iii) Is it correct to conclude that the maximum number of leaves are $153mm$ long? Why?

Q. A random survey of the number of children of various age group playing in a park was found as follows:
Draw a histogram to represent the data above.

Q. Given below are the seats won by different political parties in the polling outcome of a state assembly elections:

Political Party	A	B	C	D	E	F
Seats Won	75	55	37	29	10	37

(i) Draw a bar graph to represent the polling results.
(ii) Which political party won the maximum number of seats?

Q. A survey conducted by an organisation for the cause of illness and death among the women between the ages $15-44$ (in years) worldwide, found the following figures (in %):
(i) Represent the information given above graphically.
(ii) Which condition is the major cause of women's ill health and death worldwide?
(iii) Try to find out, with the help of your teacher, any two factors which play a major role in the cause in (ii) above being the major cause.

Q. The following data on the number of girls (to the nearest ten) per thousand boys in different sections of Indian society is given below.
(i) Represent the information above by a bar graph.
(ii) In the classroom discuss what conclusions can be arrived at from the graph.

Q. The following table gives the life times of $400$ neon lamps:
(i) Represent the given information with the help of a histogram.
(ii) How many lamps have a life time of more than $700$ hours?

Q. The following observations have been arranged in ascending order. If the median of the data is $63$, find the value of $x$.
$29,32,48,50,x,x+2,72,78,84,95$

Q. In a mathematics test given to $15$ students, the following marks (out of $100$) are recorded:
$41,39,48,52,46,62,54,40,96,52,98,40,42,52,60$
Find the mean, median and mode of this data.

Q. The following number of goals were scored by a team in a series of $10$ matches:
$2,3,4,5,0,1,3,3,4,3$
Find the mean, median and mode of these scores.

Q. Find the mode of $14,25,14,28,18,17,18,14,23,22,14,18$.