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by romitvsingh » Wed Nov 23, 2011 11:05 pm
A man can hit a target once in 4 shots. If he fires 4 shots in succession, what is the probability that he will hit his target?

1. 1

2. 1/256

3. 81/256

4. 175/256

5.144/256
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by Anurag@Gurome » Wed Nov 23, 2011 11:18 pm
romitvsingh wrote:A man can hit a target once in 4 shots. If he fires 4 shots in succession, what is the probability that he will hit his target?

1. 1

2. 1/256

3. 81/256

4. 175/256

5.144/256
The man can hit the target if he hits it 1 time, 2 times, 3 times or all the 4 times and he will not be considered to hit the target if he does not hit the target even 1 time.
Probability that he will hit the target in one shot = ¼
So, probability that he will not hit the target in one shot = 1 - ¼ = ¾
Probability that he will not hit the target in all 4 shots = ¾ * ¾ * ¾ * ¾ = 81/256
Therefore, probability that he will hit the target at least 1 time = 1 - 81/256 = [spoiler]175/256[/spoiler]

The correct answer is 4.
Anurag Mairal, Ph.D., MBA
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