Solve for x
x=4.2
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4x=16.8
Combine 3.5x and 0.5x to get 4x.
x=\frac{16.8}{4}
Divide both sides by 4.
x=\frac{168}{40}
Expand \frac{16.8}{4} by multiplying both numerator and the denominator by 10.
x=\frac{21}{5}
Reduce the fraction \frac{168}{40} to lowest terms by extracting and canceling out 8.
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