SOLUTION: A small band would like to sell CDs of its music. The business manager says that it costs $340 to produce 100 CDs and $500 to produce 500 CDs. (a) Write a linear function to rep

Algebra ->  Linear-equations -> SOLUTION: A small band would like to sell CDs of its music. The business manager says that it costs $340 to produce 100 CDs and $500 to produce 500 CDs. (a) Write a linear function to rep      Log On


   



Question 1025831: A small band would like to sell CDs of its music. The business manager says that it costs $340 to produce 100 CDs and $500 to produce 500 CDs.
(a) Write a linear function to represent the cost, $C , of producing n CDs.
(b) Find the slope and the intercept of the graph of the function, and interpret their meaning.
The slope is ___ and it represents _______
The intercept is ___ and it represents _______

(c) How much does it cost to produce 750 CDs?
(d) If the band can afford to spend $900, how many CDs can it produce?

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Plot Cost on the vertical axis
Plot number of CDs on the horizontal axis
You are given 2 points: ( n, C )
( 100, 340 )
( 500, 500 )
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Use the general point-slope formula
+%28+C+-+340+%29+%2F+%28+n+-+100+%29+=+%28+500+-+340+%29+%2F+%28+500+-+100+%29+
+%28+C+-+340+%29+%2F+%28+n+-+100+%29+=+160+%2F+400+
+%28+C+-+340+%29+%2F+%28+n+-+100+%29+=+2%2F5+
multiply both sides by +5%2A%28+n+-+100+%29+
+5%2A%28+C+-+340+%29+=+2%2A%28+n+-+100+%29+
+5C+-+1700+=+2n+-+200+
+5C+=+2n+%2B+1500+
(a) +C+=+%282%2F5%29%2An+%2B+300+
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(b)
The slope measures how fast the cost increases
with the number of CDs.
For every 1 new CD produced, the cost increases by
+2%2F5+ = $.40
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The vertical intercept, where +n=0+ is +C+=+300+
$300 is the cost even if no CDs are produced ( fixed cost )
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(c)
+n+=+750+
+C+=+%282%2F5%29%2An+%2B+300+
+C+=+%282%2F5%29%2A750+%2B+300+
+C+=+2%2A150+%2B+300+
+C+=+600+
$600
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(d)
+C+=+900+
+C+=+%282%2F5%29%2An+%2B+300+
+900+=+%282%2F5%29%2An+%2B+300+
+4500+=+2n+%2B+1500+
+2n+=+3000+
+n+=+1500+
1500 CDs can be produced
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check the equation:
does it go through ( 100,340 ) ?
+C+=+%282%2F5%29%2An+%2B+300+
+340+=+%282%2F5%29%2A100+%2B+300+
+340+=+40+%2B+300+
+340+=+340+
OK
does it go through ( 500, 500 ) ?
+C+=+%282%2F5%29%2An+%2B+300+
+500+=+%282%2F5%29%2A500+%2B+300+
+500+=+200+%2B+300+
+500+=+500+
OK