**Data Handling**

**Question 1.****For which of these would you use a histogram to show the data?****(a)** The number of letters for different areas in a postman’s bag.**(b)** The height of competitors in an athletics meet.**(c)** The number of cassettes produced by 5 companies.**(d)** The number of passengers boarding trains from 7:00 a.m. to 7:00 pan. at a station.

Give reasons for each.

**Solution:**

In (b) and (d), data can be divided into class intervals. So, their histograms can be drawn.

**Question 2.****The shoppers who come to a departmental store are marked as: man (M), woman (W), boy (B) or Girl (G). The following list gives the shoppers who came during the first hour in the morning. W W W G B W W M G G M M W W W W G B M W B G G M W W M M W W W M W B W G M W W W W G W M M W W M W G W M G W M M B G G W**Make a frequency distribution table using tally marks. Draw a bar graph to illustrate it.

**Solution:**

We arrange the data in a table using tally marks as :

**Question 3.****The weekly wages (in ?) of 30 workers in a factory are :**830, 835, 890, 810, 835, 836, 869, 845, 898, 890, 820, 860, 832, 833, 855, 845, 804, 808, 812, 840, 885, 835, 835, 836, 878, 840, 868, 890, 806,840.

Using tally marks make a frequency table with intervals as 800-810, 810-820 and so on.

**Solution:**

Let us make a grouped frequency table as under :

**Question 4.****Draw a histogram for the frequency table made for the data in question 3, and answer the following questions.(i)** Which group has the maximum number of workers?

**(ii)**How many workers earn? 850 and more?

**(iii)**How many workers earn less than? 850?

**Solution:**

The histogram to the data of question 3 is as :

From the above histogram, clearly,**(i)** The group 830-840 has the maximum number of workers.**(ii)** The number of workers who earn ₹ 850 and more are 1 + 3 + 1 + 1 + 4, i.e., 10.**(iii)** The number of workers who earn less than ₹ 850 are 3 + 2 + 1 + 9 + 5, i.e., 20.

**Question 5.**

The number of hours for which students of a particular class watched television during holidays is shown through the given graph (** on previous page**).

**Answer the following:****(i)** For how many hours did the maximum number of students watch TV?**(ii)** How many students watched TV for less than 4 hours?**(iii)** How many students spend more than 5 hours in watching TV?

**Solution:**

Clearly from the given histogram, we find that**(i)** The maximum number of students watch TV for 4 – 5 hours.**(ii)** The number of students who watch TV for less than 4 hours are 4 + 8 + 22 = 34.**(iii)** The number of students who spend more than 5 hours in watching TV are 8 + 6 = 14.