SOLUTION: A family on vacation booked three different types of rooms at a hotel, a standard, double and a suite at an average price of US$140 per room. if they were to book only the standard

Algebra ->  Equations -> SOLUTION: A family on vacation booked three different types of rooms at a hotel, a standard, double and a suite at an average price of US$140 per room. if they were to book only the standard      Log On


   



Question 143218: A family on vacation booked three different types of rooms at a hotel, a standard, double and a suite at an average price of US$140 per room. if they were to book only the standard and the suite the average price would reduce to US$135. How much does the suite cost?
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!
You won't be able to derive a specific answer, because you have three variables and only two defined relatiionships.

Cost of standard: x
Cost of double: y
Cost of suite: z

Average of the 3 is 140, so %28x%2By%2Bz%29%2F3=140

Average of standard and suite is 135, so %28x%2Bz%29%2F2=135

So you can say that x%2By%2Bz=420 and x%2Bz=270.

So x=270-z

Substituting:

270-z%2By%2Bz=420 which is to say y=150, so we know the price of a double, but as for the standard and suite, all you know is that they add up to 270. The standard could be $1 and the suite $269, or the standard could be $90 and the suite $180 -- or any other combination that totals 270. So all you can say for sure about the cost of the suite is that it is $270 minus the cost of the standard -- whatever it is.

From a practical point of view, you would expect the suite to be greater than $150. After all, who would then book a double room if you could get the suite for the same money? By the same logic, the standard room must be less than $120 otherwise the suite could not be greater than $150.

So, for the suite, the cost must be an element of the set of all z such that z * 100 is an integer (can't make change smaller than a penny), 150 < z << 270. (<< means 'a lot less than'). z has to be 'a lot less than' 270, otherwise the hotel would be charging too little for the standard rooms.