Page 101 - Mathematics Class - XI

3. When a coin is tossed three times, the sample space is
S = {HHH, HHT, HTH, HTT, THH, THT, TTH, TTT}
Number of elements in S = 8 = 2 3

Fig. (c)

4. When a coin is tossed four times, the sample space is
 HHHH, HHHT, HHTH, HHTT, HTHH, HTHT, HTTH, HTTT,
S =  
 THHH, THHTT, THTH, THTT, TTHH, TTHT, TTTH, TTTT 
Number of elements in S = 16 = 2 and so on.
4

Fig. (d)

OBSERVATION
1. Number of elements in sample space, when a coin is tossed once = 2 = 2 1
2. Number of elements in sample space, when a coin is tossed two times = 4 = 2 2

3. Number of elements in sample space, when a coin is tossed three times = 8 = 2 3
4. Number of elements in sample space, when a coin is tossed four times = 16 = 2 4

CONCLUSION
This activity shows the number of elements in a sample space, when a coin is tossed once, twice, thrice and four
times, which can be extended to n number of times.

APPLICATION
This activity is useful in determining Knowledge Booster
the probabilities of different events The probability of flipping heads or tails is equally likely in each individual toss:
associated with the sample space. P (H) = P(T) = 1/2

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