# Maths doubts

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## Maths doubts

 This post was updated on . Please explain how to do these. Thank you :) 1) At the end of the day, a bakery gives everything that is unsold to food banks for the needy. If it has 12 apple pies left at the end of a given day, in how many different ways can it distribute these pies among six food banks for the needy? Also, in how many different ways can the bakery distribute the 12 apple pies if each of the six food banks is to receive at least one pie? 2) A carton of 15 light bulbs contains one that is defective. In how many ways can an inspector choose 3 of the bulbs and get a) one that is defective 91b) non-defective ones 364 “Operator! Give me the number for 911!”
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## Re: Maths doubts

 1st apple pie can go to any1 of  the 6 food banks....similarly 2nd apple pie can go to any1 of 6 diff food banks....similarly 3rd and so on so total ways =6*6*6*6...12 times=6^12 In the 2nd part...every bank must hav atleast 1 pie...so 1st of all giv 6 pies to 6 diff banks...since all apple pies are same this can b done only in 1 way nkw distribute the remaining six in similar way discussed in 1st part of the ques ...6*6*...6 times=6^6 is the total no. Of ways Akshay Jain Masters in Economics Delhi School of Economics 2013-15
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## Re: Maths doubts

 1.If pies are indistinguishible, then a) 17C5 b) If at least one should be given to each, 11C5
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## Re: Maths doubts

 This post was updated on . @Tuski, please let me know what do you mean by "not the ones that are not defective ". Thanks. @Tuski, thanks for update.