SOLUTION: y = 80.7 - 11 ln x, 100 ≤ x ≤ 1500 which approximates the minimum required ventilation rate in terms of the air space per child in a public school classroom. In the model, x is

Algebra ->  Exponential-and-logarithmic-functions -> SOLUTION: y = 80.7 - 11 ln x, 100 ≤ x ≤ 1500 which approximates the minimum required ventilation rate in terms of the air space per child in a public school classroom. In the model, x is      Log On


   

Question 1148774: y = 80.7 - 11 ln x, 100 ≤ x ≤ 1500 which approximates the minimum required ventilation rate in terms of the air space per child in a public school classroom. In the model, x is the air space per child in cubic feet and y is the ventilation rate in cubic feet per minute.
a)Estimate the required rate of ventilation in a room with 300 cubic feet of air space per child ... (answer is 17.96 cubic feet/min/child)
b) A classroom of 30 students has an air conditioner system that moves 450 cubic feet of air per minute. Find rate of ventilation ... (answer is 15 cubic feet/min/student)
c) Use part a) to estimate the minimum required air space per child for the classroom in part b) ...... That's what I need help with
Answer by ikleyn(52814) About Me  (Show Source):
You can put this solution on YOUR website!
.

As I understand your post, you just know how to solve a) and b), and your question relates to part c) ONLY.


If so, then simply substitute  y= 17.96 (obtained in a) ) into the given formula and find x from this equation.


So, your equation is in this case


    17.96 = 80.7 - 11*ln(x).


It implies then


    ln(x) = %2880.7+-+17.96%29%2F11 = 5.70


    x                   = e%5E5.70 = 2.72%5E5.70 = 299.9 cubic feet per child = 300 cubic feet per child.


To get understanding why and how this solution works, you simply need to read ATTENTIVELY the condition 
of the problem one, two, three times, until all conceptions become clear to you.

Solved.