Page 97 - Mathematics Class - XI

Unit V St
Statistics and Probabilityatistics and Probability

TOPIC - 13: Probability

ACTIVITY 13.1

OBJECTIVE
To write the sample space, when a die is rolled once, twice, ...

MATERIAL REQUIRED
 A die  Pencil/Pen
 White paper  Plastic discs, marked with 1, 2, 3, 4, 5 or 6

PRE-REQUISITE KNOWLEDGE
1. Knowledge of sample space
2. Knowledge of faces of a die

PROCEDURE
1. Throw a die once. The number on its top will be 1, 2, 3, 4, 5 or 6.
2. On the white paper, make a tree diagram showing its six branches with number 1, 2, 3, 4, 5 or 6 (Fig. (a)).

3. Write the sample space of these outcomes on the paper.
4. Throw a die twice. It can fall in any of the 36 ways.
5. On the paper, make a tree diagram to represent the outcomes (Fig. (b)).
6. Write the sample space of these outcomes on the paper.

7. Repeat the similar experiment by throwing a die 3 times and so on and write the sample space of the
outcomes by making a tree diagram.

DEMONSTRATION
1. If a die is thrown once, the sample space is S = {1, 2, 3, 4, 5, 6}

Fig. (a)
Number of elements in S = 6 = 6 1

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