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wardas
Nov 27, 2009, 08:44 AM
A theatre has 700 seats. The orchestra seats sell for $40 each, the main seats sell for $25 each, and the balcony seats seel for $20 each. When all orchestra, main, and balcony seats are sold, the theatre collects $18,450. When half the orchestra seats and all the main and balcony seats sell, then the theatre collects 15,650. How many orchestra, main, and balcony seats are available?
Curlyben
Nov 27, 2009, 08:46 AM
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wardas
Nov 27, 2009, 09:03 AM
Curlyben:
I definitely have attempted this. I am coming up in circles. I solved for o(orchestra) first to come up with o = 700 -m -b. Then I substituted o with the above equation to solve for b (trying to get the equation into two variables). My answer came to b=477.5 - .75m. Then, I solved for m (main seats) which came to m = 839.58. I AM LOST since there are only 700 seats to begin with (m cannot possibly be 839.58). So, as you can see you have no worries that I have not tried this one.
galactus
Nov 27, 2009, 10:09 AM
A theatre has 700 seats. The orchestra seats sell for $40 each, the main seats sell for $25 each, and the balcony seats seel for $20 each. When all orchestra, main, and balcony seats are sold, the theatre collects $18,450. When half the orchestra seats and all the main and balcony seats sell, then the theatre collects 15,650. How many orchestra, main, and balcony seats are available?
Let O=# of orchestra seats, M=# main seats. B=# balcony seats.
Then, we have three equations with three unknowns.
The third constraint says that when 'half' the orchestra seats are sold, That would be O/2.
Which leaves 40(O/2)=20O in the third equation.
O+M+B=700
40O+25M+40B=18450
20O+25M+20B=15650
Solve away.
mathwiz3502
Nov 28, 2009, 06:10 AM
The difference between equation 2 and 3 is
20o and 2800
so
20o=2800
so
o=140
take out of first equation
m+b=560
and 3rd equation
25m+20b=12850
which makes m=330 and b=230 and o=140