There are 5 apples in a bag. 4 apples are good but 1 apple is rotten.

Question

There are 5 apples in a bag. 4 apples are good but 1 apple is rotten. If you take out 2 apples from the bag, what is the probability that 1 apple selected is rotten?

A.  \frac{1}{3}

B.  \frac{1}{4}

C.  \frac{2}{5}  
 
D.  \frac{3}{5}

E.  \frac{1}{7}

ThatDudeKnows · Answer

We "win" by picking the rotten apple. We could do that by picking the rotten one first and a good one second, or by picking a good one first and the rotten one second. But there is only one way to "lose": pick a good one first and a good one second. So let's find the probability of "losing."

What's the probability of picking a good one first? 4/5.
Once we've done that, what's the probability of picking a good one second? 3/4.

4/5 * 3/4 = 3/5

That's the probability of "losing," so the probability of "winning" is 2/5.

Answer choice C.

Archit3110 · Answer

good apples are 4 and 1 is bad apple
1 is bad apple from 2 
4/5 * 1/4 * 2c1 ; 2/5
option C

anisium · Answer

If we label all the apples from 1 to 5 and the 5th apple is rotten, there are 20 possible ways to take out 2 apples. If we take out the 5th apple first, we can then take out the second apple from the remaining 1-4 apples, which gives us 4 possible ways. If we take out the rotten apple second, there are also 4 possible ways to take out the first apple. Therefore, the probability of selecting a rotten apple as the second one is 8/20 or 2/5.

So  C

There are 5 apples in a bag. 4 apples are good but 1 apple is rotten.

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There are 5 apples in a bag. 4 apples are good but 1 apple is rotten.

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