document.write( "Question 997308: how do I solve a number is decreased by 30% and then doubled to be 91. What was the original number? \n" ); document.write( "

Algebra.Com's Answer #615458 by KMST(5328) $\"\"$ $\"About$

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$\"x\"$ = the original number
\n" ); document.write( "When it is decreased by $\"%2230%25%22\"$ , what is left is
\n" ); document.write( " $\"%22100%25%22-%2230%25%22=%2270%25%22=70%2F100=0.7\"$ of $\"x\"$ .
\n" ); document.write( "That is $\"0.7x\"$ .
\n" ); document.write( "When $\"0.7x\"$ is doubled, the result is
\n" ); document.write( " $\"2%2A%280.7x%29\"$ , and that equals $\"91\"$ .
\n" ); document.write( "The equation that state that is
\n" ); document.write( " $\"2%2A%280.7x%29=91\"$ .
\n" ); document.write( "Solving:
\n" ); document.write( " $\"2%2A%280.7x%29=91\"$ can be simplified to $\"1.4x=91\"$ , because
\n" ); document.write( " $\"2%2A%280.7x%29=91\"$ <--> $\"%282%2A0.7%29x=91\"$ <--> $\"1.4x=91\"$ .
\n" ); document.write( "then,
\n" ); document.write( " $\"1.4x=91\"$ --> $\"x=91%2F1.4\"$ --> $\"x=65\"$ \n" ); document.write( "

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