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Question
Two coins are tossed simultaneously 100 times and the outcomes are as given below:
| Outcomes | Two heads (H, H) |
Exactly one head (H T or T H) |
No head (T T) |
| No. of times | 21 | 55 | 24 |
If the same pair of coins is tossed again at random, find the probability of getting:
(i) two heads
(ii) exactly one head
(iii) no head.
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Solution
(i) Here, the total number of trials = 100 times
Number of heads got (H, H) = 21
`∴ "P(E)" ="Number of trials in which two heads occurs"/"Total number of trials"=21/100`
(ii) Total number of trials = 100 times
Number of extractly one heads = 55
∴ P(E) =`55/100=11/20`
(iii) Total number of trials = 100 times
Number of heads = 24
∴ Probability =`24/100=16/25`
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