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A customer wants to buy a total of 8kg rice of two varieties A an
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Updated on: 27 Apr 2018, 06:04
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3 deadly mistakes you must avoid in Probability  Exercise Question #22 A customer wants to buy a total of 8kg rice of two varieties A and B. If he can buy each type of rice only in integral multiples of 1 kg then what is the probability that he will buy at least 2 kg rice of each variety? Optionsa) 1/3 b) 4/9 c) 5/9 d) 5/8 e) 2/3 To solve question 3:Question 3 To read the article: 3 deadly mistakes you must avoid in Probability
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A customer wants to buy a total of 8kg rice of two varieties A an
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Updated on: 29 Apr 2018, 02:35
Solution Given:• The customer wants to buy 8 kg of rice. • The rice is of two types A and B. • The customer can buy each type of rice only in integral multiples of a kg. To find:• The probability such that the customer buys 2kg rice of each variety. Approach and Working: We can solve this problem from two methods: • By calculating the probabilities of the independent cases
o 2 kg Rice A and 6 kg rice B o 3 kg Rice A and 5 kg rice B o 4 kg Rice A and 4 kg rice B o 5 kg Rice A and 3 kg rice B o 6 kg Rice A and 2 kg rice B • By nonevent method
o P (customer buys 2kg rice of each variety) = 1 P(customer buys 0 kg rice of one variety) P(customer buys 1 kg rice of one variety) Clearly, the 2nd method reduces a lot of calculation. P(customer buys 0 kg rice of one variety):
• There are 2 possible ways in which he can buy 0 kg rice of one variety.
o When he buys 8 kg rice of type A. o When he buys 8 kg rice of type A. • Thus, P (customer buys 0 kg rice of one variety) = 2/9 P(customer buys 1 kg rice of one variety):• There are 2 possible ways in which he can buy 1 kg rice of one variety.
o When he buys 1 kg rice of type A and 1 kg rice of type B. o When he buys 1 kg rice of type B and 7 kg rice of type B. • Thus, P (customer buys 0 kg rice of one variety) = 2/9
Hence, P (customer buys 2kg rice of each variety) = 1 2/92/9= 5/9 Hence, the correct answer is option C. Answer: C
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Re: A customer wants to buy a total of 8kg rice of two varieties A an
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26 Apr 2018, 05:40
Total no. of cases lie from the range of (8,0) to (0,8) => 9 cases and no. of favorable ones would be (2,6),(3,5),(4,4),(5,3), and (6,2) => probability=5/9



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Re: A customer wants to buy a total of 8kg rice of two varieties A an
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27 Apr 2018, 01:01
Integral solutions to the equation A+B = x = x+21 C 1 Since A , B have to be at least 2 each the equation becomes A+B=4. Number of solutions = 5C1 = 5. Total possible solutions = 9C1 = 9. Hence C.
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Re: A customer wants to buy a total of 8kg rice of two varieties A an
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27 Apr 2018, 03:27
attari92 wrote: Total no. of cases lie from the range of (8,0) to (0,8) => 9 cases and no. of favorable ones would be (2,6),(3,5),(4,4),(5,3), and (6,2) => probability=5/9 hi i have a confusion...here.. how one can take (8,0) and (0,8) it is given a person need two take 8 kg of rice of two varieties...there must be two varieties in 0,8 and 8,0 the variety is only one..



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Re: A customer wants to buy a total of 8kg rice of two varieties A an
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27 Apr 2018, 04:04
viv007 wrote: attari92 wrote: Total no. of cases lie from the range of (8,0) to (0,8) => 9 cases and no. of favorable ones would be (2,6),(3,5),(4,4),(5,3), and (6,2) => probability=5/9 hi i have a confusion...here.. how one can take (8,0) and (0,8) it is given a person need two take 8 kg of rice of two varieties...there must be two varieties in 0,8 and 8,0 the variety is only one.. I put the two varieties in an ordered pair, just a gesticulation of representation. And, there isn't anything wrong in considering range from (8,0) to (0,8) as it symbolizes the entire sample space.



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Re: A customer wants to buy a total of 8kg rice of two varieties A an
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29 Apr 2018, 02:36



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A customer wants to buy a total of 8kg rice of two varieties A an
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30 Apr 2018, 18:42
EgmatQuantExpert wrote: Hey everyone,
The official answer to the question has been posted.
Regards, Ashutosh Can you rephrase the question to "he needs to buy 8 kg. There are two kinds of rice..."? Otherwise the question sounds ambiguous, since he have to buy 8 kg of both kinds, and people are confused. Thanks
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Re: A customer wants to buy a total of 8kg rice of two varieties A an
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28 May 2018, 11:01
For calculating the total number of outcomes, is counting the best method? Can't figure out any alternative approach.



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Re: A customer wants to buy a total of 8kg rice of two varieties A an
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29 May 2018, 00:41
EgmatQuantExpert wrote: Solution Given:• The customer wants to buy 8 kg of rice. • The rice is of two types A and B. • The customer can buy each type of rice only in integral multiples of a kg. To find:• The probability such that the customer buys 2kg rice of each variety. Approach and Working: We can solve this problem from two methods: • By calculating the probabilities of the independent cases
o 2 kg Rice A and 6 kg rice B o 3 kg Rice A and 5 kg rice B o 4 kg Rice A and 4 kg rice B o 5 kg Rice A and 3 kg rice B o 6 kg Rice A and 2 kg rice B • By nonevent method
o P (customer buys 2kg rice of each variety) = 1 P(customer buys 0 kg rice of one variety) P(customer buys 1 kg rice of one variety) Clearly, the 2nd method reduces a lot of calculation. P(customer buys 0 kg rice of one variety):
• There are 2 possible ways in which he can buy 0 kg rice of one variety.
o When he buys 8 kg rice of type A. o When he buys 8 kg rice of type A. • Thus, P (customer buys 0 kg rice of one variety) = 2/9 P(customer buys 1 kg rice of one variety):• There are 2 possible ways in which he can buy 1 kg rice of one variety.
o When he buys 1 kg rice of type A and 1 kg rice of type B. o When he buys 1 kg rice of type B and 7 kg rice of type B. • Thus, P (customer buys 0 kg rice of one variety) = 2/9
Hence, P (customer buys 2kg rice of each variety) = 1 2/92/9= 5/9 Hence, the correct answer is option C. Answer: CHello  i dont understand how to get the 9 denominator, mind to explain ?




Re: A customer wants to buy a total of 8kg rice of two varieties A an &nbs
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29 May 2018, 00:41






