Page 100 - Mathematics Class - XI

ACTIVITY 13.2

OBJECTIVE
To write the sample space, when a coin is tossed once, two times, three times, four times.

MATERIAL REQUIRED
 A coin  White paper
 Pen/pencil  Plastic discs, marked with Head (H) and Tail (T)

PRE-REQUISITE KNOWLEDGE
1. Knowledge of sample space
2. Knowledge of tree diagram

PROCEDURE
1. Toss a coin once. It can have two outcomes—Head or Tail.
2. Make a tree diagram to represent the two branches of a tree (Fig. (a)).
3. Write its sample space on the paper.

4. Toss a coin twice. It can have four outcomes (Fig. (b)).
5. Repeat the experiment with tossing the coins three times, four times, ..., n times and write their sample
spaces (Figs. (c) and (d)).

DEMONSTRATION
1. When a coin is tossed once, the sample space is S = {H, T}
Number of elements in S = 2 = 2 1

Fig. (a)

2. When a coin is tossed two times, the sample space is
S = {HH, HT, TH, TT}
Number of elements in S = 4 = 2 2

Fig. (b)

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