Counting

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Counting

by Arun6765 » Thu Mar 09, 2017 9:12 am
4.Amit has five friends: 3 girls and 2 boys. Amit's wife also has 5 friends : 3 boys and 2
girls. In how many maximum number of different ways can they invite 2 boys and 2 girls such
that two of them are Amit's friends and two are his wife's? [spoiler](Ans:c)[/spoiler]
(a) 24
(b) 38
(c) 46
(d) 58
(e)68

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Counting

by [email protected] » Thu Mar 09, 2017 9:19 am
Hi Arun6765,

In the future, you should make sure to post questions into the proper sub-Forums. For example, the PS Forum is here:

https://www.beatthegmat.com/problem-solving-f6.html

This specific type of prompt is relatively rare (you probably won't see it on Test Day). From a 'math standpoint', you can solve it by using the Combination Formula in a really specific way:

The question asks for the number of 'groups' that can be formed of 2 boys and 2 girls (with the added condition that 2 people come from Amit's friends and 2 come from his wife's friends). There are 3 ways that this can occur....

1) 2 boys from Amit; 2 girls from his wife
2) 2 girls from Amit; 2 boys from his wife
3) 1 boy and 1 girl from each

1st option = (2C2)(2C2) = (1)(1) = 1 option
2nd option = (3C2)(3C2) = (3)(3) = 9 options
3rd option = (3)(2)(3)(2) = 36 options

Total = 1+9+36 = 46

Final Answer: C

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by AlexBarret » Thu May 11, 2017 11:43 am
Arun6765 wrote:4.Amit has five friends: 3 girls and 2 boys. Amit's wife also has 5 friends : 3 boys and 2
girls. In how many maximum number of different ways can they invite 2 boys and 2 girls such
that two of them are Amit's friends and two are his wife's? [spoiler](Ans:c)[/spoiler]
(a) 24
(b) 38
(c) 46
(d) 58
(e)68
Such an original quastion! Why do I have to think about maximum number of different ways to invite the friends? Is it so important?))

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by [email protected] » Wed Jul 05, 2017 12:05 am
AlexBarret wrote:
Arun6765 wrote:4.Amit has five friends: 3 girls and 2 boys. Amit's wife also has 5 friends : 3 boys and 2
girls. In how many maximum number of different ways can they invite 2 boys and 2 girls such
that two of them are Amit's friends and two are his wife's? [spoiler](Ans:c)[/spoiler]
(a) 24
(b) 38
(c) 46
(d) 58
(e)68
Such an original quastion! Why do I have to think about maximum number of different ways to invite the friends? Is it so important?))
A quaint one too - who gets invited to anything any more? It seems like people just digitally announce events (or maybe I've been living in California too long ...)

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by Risfy1994 » Fri Dec 29, 2017 2:18 am
Hi there! To my mind, the right answer is c, but I am not sure at all. So which one is correct?

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Re: Counting

by Tony Mai » Fri Dec 11, 2020 4:24 am
Who has the answer to how many results yet. Can you share it with me?