(x+80) \div 90 \% =(x-70) \div 75 \%
Solve for x
x=820
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\frac{\left(x+80\right)\times 100}{90}=\frac{x-70}{\frac{75}{100}}
Divide x+80 by \frac{90}{100} by multiplying x+80 by the reciprocal of \frac{90}{100}.
\left(x+80\right)\times \frac{10}{9}=\frac{x-70}{\frac{75}{100}}
Divide \left(x+80\right)\times 100 by 90 to get \left(x+80\right)\times \frac{10}{9}.
x\times \frac{10}{9}+80\times \frac{10}{9}=\frac{x-70}{\frac{75}{100}}
Use the distributive property to multiply x+80 by \frac{10}{9}.
x\times \frac{10}{9}+\frac{80\times 10}{9}=\frac{x-70}{\frac{75}{100}}
Express 80\times \frac{10}{9} as a single fraction.
x\times \frac{10}{9}+\frac{800}{9}=\frac{x-70}{\frac{75}{100}}
Multiply 80 and 10 to get 800.
x\times \frac{10}{9}+\frac{800}{9}=\frac{\left(x-70\right)\times 100}{75}
Divide x-70 by \frac{75}{100} by multiplying x-70 by the reciprocal of \frac{75}{100}.
x\times \frac{10}{9}+\frac{800}{9}=\left(x-70\right)\times \frac{4}{3}
Divide \left(x-70\right)\times 100 by 75 to get \left(x-70\right)\times \frac{4}{3}.
x\times \frac{10}{9}+\frac{800}{9}=x\times \frac{4}{3}-70\times \frac{4}{3}
Use the distributive property to multiply x-70 by \frac{4}{3}.
x\times \frac{10}{9}+\frac{800}{9}=x\times \frac{4}{3}+\frac{-70\times 4}{3}
Express -70\times \frac{4}{3} as a single fraction.
x\times \frac{10}{9}+\frac{800}{9}=x\times \frac{4}{3}+\frac{-280}{3}
Multiply -70 and 4 to get -280.
x\times \frac{10}{9}+\frac{800}{9}=x\times \frac{4}{3}-\frac{280}{3}
Fraction \frac{-280}{3} can be rewritten as -\frac{280}{3} by extracting the negative sign.
x\times \frac{10}{9}+\frac{800}{9}-x\times \frac{4}{3}=-\frac{280}{3}
Subtract x\times \frac{4}{3} from both sides.
-\frac{2}{9}x+\frac{800}{9}=-\frac{280}{3}
Combine x\times \frac{10}{9} and -x\times \frac{4}{3} to get -\frac{2}{9}x.
-\frac{2}{9}x=-\frac{280}{3}-\frac{800}{9}
Subtract \frac{800}{9} from both sides.
-\frac{2}{9}x=-\frac{840}{9}-\frac{800}{9}
Least common multiple of 3 and 9 is 9. Convert -\frac{280}{3} and \frac{800}{9} to fractions with denominator 9.
-\frac{2}{9}x=\frac{-840-800}{9}
Since -\frac{840}{9} and \frac{800}{9} have the same denominator, subtract them by subtracting their numerators.
-\frac{2}{9}x=-\frac{1640}{9}
Subtract 800 from -840 to get -1640.
x=-\frac{1640}{9}\left(-\frac{9}{2}\right)
Multiply both sides by -\frac{9}{2}, the reciprocal of -\frac{2}{9}.
x=\frac{-1640\left(-9\right)}{9\times 2}
Multiply -\frac{1640}{9} times -\frac{9}{2} by multiplying numerator times numerator and denominator times denominator.
x=\frac{14760}{18}
Do the multiplications in the fraction \frac{-1640\left(-9\right)}{9\times 2}.
x=820
Divide 14760 by 18 to get 820.
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