Answer:
Each microphine cost $21
Step-by-step explanation:
Equation: (38+c) 6 = 354
(38+c) 6 = 354 distribute 6 into 38 and c
38*6 + c*6
\/ \/
228 + 6c = 354 Subtract 228
-228 -228
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6c = 126 divide 6
÷6 ÷6
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c = 21
:)