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Re: Jane must select three different items for each dinner she [#permalink]
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kunalkmr62 wrote:
I used the following approach. Can someone tell what is wrong with this approach -:

1 veg should always be there = 5 ways in which this can be selected
now we are left with 4 veg and 4 non-veg dishes
so no of ways in which 2 items can be chosen from a total of 8 = 8C2= 28
hence total no of ways = 28*5 = 140



you are going wrong because there are repetitions in it..
let me give you an example with a smaller set of numbers...

say 2 veg A and B AND 1 non veg C..
so atleast 1 veg should be there and we are looking for ways to choose two ..
By your method..
choose one of two say 2C1 and then 1 from remaining veg and 1 non veg so 1 out of two therefore 2C1
total 2C1*2C1=2*2=4
But is it so...NO
let us see the 4 ways ..
1) choose A, the other could be B or C.. AB and AC
2) choose B, the other could be A or C.. BA and BC
Isnt AB and BA same, so repetitions...

actual answer would be
both veg - 1
one veg and one non veg - 2C1*1=2
total 3

Hope it helps
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Re: Jane must select three different items for each dinner she [#permalink]
By my method , to chose 1 veg we have 2 ways and now we need to chose 2 items from the remaining 2 , which can be done in only 1 way or 2C2 ways.
Hence total no of dinner possible = 2 . Same as yours

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Re: Jane must select three different items for each dinner she [#permalink]
Expert Reply
kunalkmr62 wrote:
By my method , to chose 1 veg we have 2 ways and now we need to chose 2 items from the remaining 2 , which can be done in only 1 way or 2C2 ways.
Hence total no of dinner possible = 2 . Same as yours

Posted from my mobile device Image


No our answers are different, my answer here would be to choose two out of 3 =3C2=3..

Anyways the reason to tell you about that was the flaw in the approach and why you were getting wrong answers.
If you have got it, it is good.
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Re: Jane must select three different items for each dinner she [#permalink]
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I guess from a total of 8 = 8C2= 28 and hence total no of ways = 28*5 = 140. If you are looking for the top hot air fryer, then https://bestairfryer.reviews/gourmia/ is your choice and you have landed on the right page. It is always wise to compare the products and read the full verdict of a particular appliance. This can help you to make an unbiased decision.
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Re: Jane must select three different items for each dinner she [#permalink]
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Hi, my approach to this question was a little different. Can you help me identify where I went wrong please?

Since there are three dishes Jane has to pick of which one has to be vegetarian I used the slot method.

The first combination is veggie, meat, meat. There are 5 veggie dishes she can pick from so the first slot is 5. Then there are 4 meat dishes she can pick from so the second slot is 4. Lastly, there are only 3 meat dishes left that she can pick the second dish from so the third slot is 3. This gives a total of 60.

__5__ * __4__ * __3__

Then the other combination is veggie, veggie, meat which gives you a total of 80.

__5__ * __4__ * __4__

The third combination is veggie, veggie, veggie which gives you a total of 60.

__5__ * __4__ * __3__

60+80+60 = 200 which isn't even an option. Can someone tell me where I went wrong?

Thank you!
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Re: Jane must select three different items for each dinner she [#permalink]
Based on the ratio of the dishes, I would choose option b
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Re: Jane must select three different items for each dinner she [#permalink]
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Re: Jane must select three different items for each dinner she [#permalink]
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