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richs_ca
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 Posted: Fri May 02, 2008 11:17 am Post subject: Probability Problem |
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In a survey of students, each student selected from a list of 12 songs the 2 that the student liked best. If each song was selected 4 times, how many students were surveyed?
a) 96
b) 48
c) 32
d) 24
e) 18
I don't even know where to start!
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simplyjat
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| Posted: Fri May 02, 2008 11:20 am Post subject: |
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Total number of songs = 12
Each song was selected 4 times, so total selections = 12*4 = 48
One student can select 2 songs, so number of students = 48/2 = 24
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chipjet
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| Posted: Fri Jun 13, 2008 12:49 pm Post subject: |
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The best approach to this is to think what exactly is happening. If each student (x) gets to pick 2 songs each, that product can be divided by 12 to get to 4.
In a formula:
(2x)/12 = 4
Solve for x = 24 |
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