Question

The number of hours, spent by a school boy on different activities in a working day, is given below:

Activities	Sleep	School	Home	Play	Others	Total
Number of hours	8	7	4	2	3	24

Present the information in the form of a pie-chart.

Answer 1

We know:
Central angle of a component = (component value / sum of component values $\times$ 360)
Here, total number of hours = 24
Thus, the central angle for each component can be calculated as follows:

Activity	Number of hours	Sector angle
Sleep	8	8/24 $\times$ 360 = 120o
School	7	7/24 $\times$ 360 = 105o
Home	4	4/24 $\times$ 360 = 60o
Play	2	2/24 $\times$ 360 = 30o
Others	3	3/24 $\times$ 360 = 45o

Now, the pie chat that represents the given data can be constructed by following the steps given below:
Step 1 : Draw a circle of an appropriate radius.
Step 2 : Draw a vertical radius of the circle drawn in step 1.
Step 3 : Choose the largest central angle. Here, the largest central angle is 120^o. Draw a sector with the central angle 120^o in such a way that one of its radii coincides with the radius drawn in step 2 and another radius is in its counter-clockwise direction.
Step 4 : Construct other sectors representing other items in the clockwise direction in descending order of magnitudes of their central angles.
​Step 5 : Shade the sectors with different colours and label them as shown as in the figure below.