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\ 06-Jan-2025 Bharat Arora Proof-6 Reader’s Sign _______________________ Date __________

5. For the development of basic infrastructure in a district, a project of `108 crore approved by the
Development Bank is as follows

Item head Road Electricity Drinking water Sewage
Amount (in crore `) 43.2 16.2 27.0 21.6

Draw a pie chart for this data.
6. In the timetable of a school, periods allotted per week to different subjects are given below.

Subject Hindi English Maths Science Social Science Computer Science Sanskrit

Period Allotted 6 8 8 8 7 4 4

Draw a pie chart for this data.

Chance and Probability

In real life, there are situations that are ‘certain to happen’, ‘impossible to happen’ and ‘may happen,
but not certain’. An uncertain situation may be ‘more likely to happen’, ‘less likely to happen’ and
‘equally likely to happen’.

For example,
• The match may happen but not certain due to rain because it is heavily clouded.

• Today, India may be more likely to win the match if the batsmen score well.

• Bangladesh may be less likely to win the match if the bowlers do not take wickets in power play.
• It is equally likely to get an even or odd number if we roll a die.

In the case of uncertainty, we take a chance on an event. When a fair coin is tossed before the
start of the match, we cannot predict the heads or tails. There are equal chances to have a head
or tail in tossing a coin. This is an example of a random experiment.
All the above examples convey that there is uncertainty about the occurrence of the event. This
uncertainty about what has happened or what is going to happen is known as Probability.

In this section, we shall learn more about the probability of outcomes or events associated with
random experiments only. Before that, let us review what we have learnt in the previous class.
( a) Experiment: An activity that has some well-defined results is called an experiment. The
results of the experiment obtained are known as outcomes.
( b) Trial: If an experiment is performed once, it is called a trial.

( c) Random Experiment: An experiment in which we know all the possible outcomes but
cannot predict the exact result of any trial is called a random experiment, e.g., if a dice is
thrown, the dice will show up 1, 2, 3, 4, 5, or 6. Here, we know all the outcomes but can’t
predict which number will face up after landing the dice.
( d) Event: A set of outcomes of a random experiment is called an event. If we toss a coin,
the possible outcomes are head or tail. These possible outcomes of a trial are known as
events, e.g., in a single throw of a coin, getting head is an event.

( e) Sure Event: If the occurrence of an event is certain, it is called a sure event.

109 Data Handling