Calculating p/n: Solving for the Ratio of Two Averages in a Mental Lapse

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To solve for the ratio of p to n given the average scores, the equation simplifies to p = (3/8)n. This means that for every 8 students in group n, there are 3 students in group p. The discussion highlights that without specific values for either p or n, the ratio remains as 3/8. Examples provided illustrate that if n is 24, then p is 9, and if n is 48, then p is 18. The conversation concludes with a light-hearted acknowledgment of the mental lapse due to lack of sleep.
courtrigrad
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Hello all

I am having a little mental lapse.

If the average score of p students is 70 and the average score of n students is 92, and the average of the scores of p and n is 86, what is p/n?

(70p + 92n)/ ( p + n ) = 86

70p + 92n = 86(p+n)

70p + 92n = 86p +86n
92n = 16p + 86n
6n = 16p
p = 3/8n
n= 8/3p

Where do I go from here (sorry was awake for whole night)

Thanks
 
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Unless you're given either n or p, you're done. You have the ratio between n and p.

If n is 24 students, then p is 9 students; if n is 48 students, then p is 18 students, etc.
 
You're 'home'. :smile:If
p=\frac{3}{8}n
,then
\frac{p}{n}=\frac{3}{8}

,okay??

Daniel.
 
lol

thanks dextercioby

guess it was because i stayed up
 
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