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Question 387990:   A local gym charges nonmembers $10 per hour to use the tennis courts. 
Members pay a yearly fee of $300 and $4 per hour for using the tennis 
courts. Write an equation to find how many hours, h, you must use the tennis courts to justify becoming a member.  
 
What is the equation in question #15 for the value of h? 
Kris, Thank you! 
 Answer by Theo(13342)      (Show Source): 
You can  put this solution on YOUR website! The formula for total cost is: 
T = x + y*h 
x = the membership cost. 
y = the cost per hour. 
For the non-member, the total cost is equal to: 
T = 0 + 10*h which becomes: 
T = 10*h 
For the member, the total cost is equal to: 
T = 300 + 4*h 
You want to know at what point the total cost for the member becomes less than the total cost for the non-member. 
That point is given by the equation: 
300 + 4*h < 10*h 
Subtract 4*h from both sides of this equation to get: 
300 < 10*h - 4*h 
Simplify to get: 
300 < 6*h 
Divide both sides of this equation by 6 to get: 
300/6 < h 
Simplify to get: 
50 < h 
50 < h also means h > 50. 
The total membership cost will becomes less than the total non-member cost when the number of hours is greater than 50. 
If h = 50, then the equation of: 
300 < 10*h - 4*h becomes: 
300 < 10*50 - 4*50 
Simplify this to get: 
300 < 500 - 200 
Simplify further to get: 
300 < 300 
The statement is not true because h is not greater than 50. 
Take any h greater than 50 and the equation should be true. 
Take h = 51. 
You get: 
300 < 10*51 - 4*51 
simplify this to get: 
300 < 510 - 204 
Simplify further to get: 
300 < 306 
The statement is now true.
 
 
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