Question : Three coins are simultaneously tossed 200 times with the following frequencies of different outcomes.
| Outcome | 3 Head | 2 Head | 1 Head | No Head |
| Frequency | 23 | 72 | 77 | 28 |
If the three coins are simultaneously tossed again, compute the probability of
(A) 1 Tail
(B) Less Than 2 Heads
Doubt by Aditi
Solution :
Total number of times the three coins are tossed = 200
Number of times 3 heads (or 3 Heads & 0 Tail) come = 23
Number of times 2 heads (or 2 Heads and 1 Tail) come = 72
Number of times 1 head (or 1 Head and 2 Tails) come = 77
Number of times 0 head (or 0 Head and 3 Tails) come = 28
(a)
Number of times 1 Tail come = 72
P(1 Tail)
= (No. of favourable outcomes)/(Total No. of possible outcomes)
= 72/200
= 36/100
= 0.36
(b)
Number of times outcomes are less than 2 Head (0 Head + 1 Head)
P(Less Than 2 Heads)
= 105/200
= 21/40
= 0.525