Solve for x
x=400
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x\times 0.8=80\times 4
Divide 80 by \frac{1}{4} by multiplying 80 by the reciprocal of \frac{1}{4}.
x\times 0.8=320
Multiply 80 and 4 to get 320.
x=\frac{320}{0.8}
Divide both sides by 0.8.
x=\frac{3200}{8}
Expand \frac{320}{0.8} by multiplying both numerator and the denominator by 10.
x=400
Divide 3200 by 8 to get 400.
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