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# Algebra/Algebra 1

Question
Cost for copies is a linear function of the number of copies. If 100 copies cost \$16.00,and 125 copies cost \$ 18.25, write a formula for a copy cost as a linear function of the number of copies. Then find how much it would cost to make 400 copies.
If x is the number of copies made and y is the amount charged for the copies, what is the formula for the amount.
Thanks for your help. This is a hard one.

Note that 125 copies is 25 more than 100 copies.
The difference in price is \$2.25.
Taking 2.25/25 is 9c each.
This means the 100 copies cost \$9.

If that is how much 100 copies cost, there is a \$7 cost just for using the machine.
That makes the equation for price be y = \$7 + \$0.09x where x is the number of units.
Using this to check, for x= 100, we get y = \$7 + \$9 = \$16 and
for x = 125, we get y = \$7 + \$11.25 = \$18.25.

If x = 400, we get y = \$7 + \$36 = \$43.

Algebra

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#### Scott A Wilson

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Any algebraic question you've got. That includes question that are linear, quadratic, exponential, etc.

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I have solved story problems, linear equations, parabolic equations. I have also solved some 3rd order equations and equations with multiple variables.

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Documents at Boeing in assistance on the manufacturiing floor.

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MS at math OSU in mathematics at OSU, 1986. BS at OSU in mathematical sciences (math, statistics, computer science), 1984.

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