Solve for x
x = \frac{42}{5} = 8\frac{2}{5} = 8.4
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840\times 10=x\times 1000
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 840x, the least common multiple of x,840.
8400=x\times 1000
Multiply 840 and 10 to get 8400.
x\times 1000=8400
Swap sides so that all variable terms are on the left hand side.
x=\frac{8400}{1000}
Divide both sides by 1000.
x=\frac{42}{5}
Reduce the fraction \frac{8400}{1000} to lowest terms by extracting and canceling out 200.
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