Solve for x
x=0.63
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3\times 4.2=20x
Multiply both sides of the equation by 300, the least common multiple of 100,15.
12.6=20x
Multiply 3 and 4.2 to get 12.6.
20x=12.6
Swap sides so that all variable terms are on the left hand side.
x=\frac{12.6}{20}
Divide both sides by 20.
x=\frac{126}{200}
Expand \frac{12.6}{20} by multiplying both numerator and the denominator by 10.
x=\frac{63}{100}
Reduce the fraction \frac{126}{200} to lowest terms by extracting and canceling out 2.
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