Answer:
about 4312
Step-by-step explanation:
You want the total cost for n CDs to be 3.50n.
The manufacturer will charge you 9700+1.25n, so you want these to be equal:
3.50n = 9700 +1.25n
2.25n = 9700 . . . . . . . . subtract 1.25n
n = 9700/2.25 ≈ 4311.111...
Producing 4312 CDs will make the cost per CD slightly less than $3.50.
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Producing 4311 CDs will make the cost per CD be about $3.500058. Producing 4312 CDs will bring it down to $3.499536.
