Solve for x
x=80
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0.1x+13.5=21.5
Multiply 0.45 and 30 to get 13.5.
0.1x=21.5-13.5
Subtract 13.5 from both sides.
0.1x=8
Subtract 13.5 from 21.5 to get 8.
x=\frac{8}{0.1}
Divide both sides by 0.1.
x=80
Expand \frac{8}{0.1} by multiplying both numerator and the denominator by 10. Anything divided by one gives itself.
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