21. BRAINLIEST! URGENT!
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Answer:
100
Step-by-step explanation:
here we are solving for x
first plug in 100 for the ys in the equation
0.10x + 0.10(100) = 0.18(x + 100)
simplify
0.10x + 10 = 0.18x + 18
get x by itself
-8 = 0.08x
-100 = x
so the reasonable answer here would be 100
hope this helps <3