Shooting the target

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Shooting the target

by neeti2711 » Mon Oct 22, 2012 5:06 am
The probability that a person can hit the target is 3/5 and another can hit the same target is 2/5. But the first person can fire 8 shots in the time the second can fire 10 shots. What is the probability that the person shoots the target when they fire together?
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by Brent@GMATPrepNow » Mon Oct 22, 2012 5:16 am
neeti2711 wrote:The probability that a person can hit the target is 3/5 and another can hit the same target is 2/5. But the first person can fire 8 shots in the time the second can fire 10 shots. What is the probability that the person shoots the target when they fire together?
It's unclear what this question is asking.
For example, in What is the probability that the person shoots the target when they fire together?, who is the person? Which person?
It's also unclear what "fire together" means.

What are the answer choices, and what's the source of this question?

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by Jim@StratusPrep » Mon Oct 22, 2012 5:18 am
The time does not matter for the chances of them hitting the target together. Simply multiply 2/5 * 3/5 for 6/25


P.S. I am taking some liberties with the information given as much is unclear.
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by neeti2711 » Mon Oct 22, 2012 8:07 pm
Hey Brent,

The question was in a book of questions on probability. I too had problem understanding it.. so thought of asking the experts.. I have copied the exact question.. :(

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by Brent@GMATPrepNow » Mon Oct 22, 2012 8:45 pm
neeti2711 wrote:Hey Brent,

The question was in a book of questions on probability. I too had problem understanding it.. so thought of asking the experts.. I have copied the exact question.. :(
I understand. It's an odd question. If it's asking for the probability that both people hit the target if they take one shot each, then Jim's solution is correct. However, I don't understand the role that the "8 shots vs 10 shots" information plays.

I think we'll have to just leave this one as an unsolved mystery.

Cheers,
Brent
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