OG 11 DS#55 Ice Cream Scoops

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OG 11 DS#55 Ice Cream Scoops

by drhomler » Sat Jun 23, 2007 5:19 am
Why is the answer not B

statement 2 says a total of 120 scoops are served, from the parapgraph we know each guest received either a single scoop or a double scoop therefore-S+2S=120 and S=40 so which means 40 guests received a single scoop and 40 guests were served 2 scoops for a total of 120 scoops.

Am I reading too much into this?I feel like I have seen a couple other examples were this type of thinking is necessary.
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by jayhawk2001 » Sat Jun 23, 2007 6:23 am
S+2S = 120

The above is incorrect. You cannot assume that an equal number of
guests were served single and double scoops.

You can have 40 single-scoop + 40 double-scoop for a total of 120, or
you can have 20 single scoop + 50 double-scoop again for a total of 120.
So, (2) is not sufficient.

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Re: OG 11 DS#55 Ice Cream Scoops

by bingojohn » Wed Aug 08, 2007 2:19 pm
drhomler wrote:Why is the answer not B

statement 2 says a total of 120 scoops are served, from the parapgraph we know each guest received either a single scoop or a double scoop therefore-S+2S=120 and S=40 so which means 40 guests received a single scoop and 40 guests were served 2 scoops for a total of 120 scoops.

Am I reading too much into this?I feel like I have seen a couple other examples were this type of thinking is necessary.
where is the question text... are you assuming that I have the same book and the same version of the book that you have?

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by anniev2 » Sun Feb 22, 2009 7:32 pm
The correct answer is C. However, I'd like to know how to calculate the number of guests.

The explanation goes...

Using both statements, the ratio of the number of single scoops served to the number of double scoops served can be determined (1) and used with the total number of scoops served (2) to determine the total number of guests who were served a double scoop.

Ratio of Single Scoops to Double Scoops
4:6 = 2:3
Whole is 5

If 120 scoops are served and the whole is 5, there are 24 sets.

24 x 2 = 48 guests were served a single scoop
(24 x 3)/2 = 32 guests were served a double scoop

48 + 32 = 80 guests total

Is this correct?

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by bluementor » Thu Feb 26, 2009 3:58 am
anniev2 wrote:The correct answer is C. However, I'd like to know how to calculate the number of guests.

The explanation goes...

Using both statements, the ratio of the number of single scoops served to the number of double scoops served can be determined (1) and used with the total number of scoops served (2) to determine the total number of guests who were served a double scoop.

Ratio of Single Scoops to Double Scoops
4:6 = 2:3
Whole is 5

If 120 scoops are served and the whole is 5, there are 24 sets.

24 x 2 = 48 guests were served a single scoop
(24 x 3)/2 = 32 guests were served a double scoop

48 + 32 = 80 guests total

Is this correct?
I believe total guests would be 75. Here's my explanation:

Total no. of guests = T
No. of guests with a single scoop = x
No. of guests with a double scoop = y

x + y = T

and we know from statement 1 that y = 0.6G.

so, x = 0.4T.

From statement 2:

120 = x + 2y
120 = 0.4T + 2*0.6T
120 = 1.6T
T = 75

-BM-

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by mavesum » Sat Feb 28, 2009 3:07 am
From statement 2:

120 = x + 2y
sorry BM i didnt get hows this inferred from statement 2 ?

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by bluementor » Sat Feb 28, 2009 8:58 am
mavesum wrote:
From statement 2:

120 = x + 2y
sorry BM i didnt get hows this inferred from statement 2 ?
120 scoops were given out in total. These were given out to x people (who received one scoop each) and to y people (who received 2 scoops each).

So the equation you can derive in terms of no. of scoops will be:

120 = x*(1) + y*(2)
120 = x + 2y

hth

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by mavesum » Sat Feb 28, 2009 9:56 am
yup got it now - thanks