Solve for x
x=140
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\frac{3}{20}x=21
Combine \frac{4}{5}x and -\frac{13}{20}x to get \frac{3}{20}x.
x=21\times \frac{20}{3}
Multiply both sides by \frac{20}{3}, the reciprocal of \frac{3}{20}.
x=\frac{21\times 20}{3}
Express 21\times \frac{20}{3} as a single fraction.
x=\frac{420}{3}
Multiply 21 and 20 to get 420.
x=140
Divide 420 by 3 to get 140.
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