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.Com
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(52815)   (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) =  = 5.70


    x                   =  =  = 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.


RELATED QUESTIONS

According to the American Society of Heating, Refrigerating and Air-Conditioning... (answered by CPhill)
A room requires the ventilation system to produce 8 air exchanges per hour. This means... (answered by checkley71)
11. Let x = ln 3 and y = ln 5. Write the following expressions in terms of x and y.... (answered by Alan3354)
11. Let x = ln 3 and y = ln 5. Write the following expressions in terms of x and y... (answered by josgarithmetic,greenestamps)
Express y in terms of x when: ln y - ln(y+1) = ln x (answered by jim_thompson5910)
The function Y(x)= 48.94 ln x/4.5 can be used to estimate the number of years Y(x) after (answered by stanbon)
Which equation is equivalent to y=7x^5 A. Ln(y) = ln (7) + 5 ln (x) B. Y = ln (7) + 5... (answered by Alan3354)
Express in terms of logarithms of x, y, z, or w. x^6 w --------=ln(base a) y^2 z^4 (answered by Alan3354)
Flying with the wind, a plane flew 1500 mi in 5 h. Against the wind, the plane required 6 (answered by richwmiller)