document.write( "Question 812423: 50% of 90 is the same as 40% of this number
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Algebra.Com's Answer #489162 by jsmallt9(3758) $\"\"$ $\"About$

You can put this solution on YOUR website!
When a problems mentions \"[fraction or percent] of [some number]\", the \"of\" translates into a multiplication. And if it says percent, like your problem, use the fraction or decimal equivalent of the percents. (Do not use actual percents in arithmetic!)

\n" ); document.write( "So, using 0.50 for 50%, 0.40 for 40% and x for the unknown number, \"50% of 90 is the same as 40% of this number\" translates into:
\n" ); document.write( "0.50 * 90 = 0.40 * x
\n" ); document.write( "Now we just solve for x. First we simplify the left side:
\n" ); document.write( "45 = 0.40x
\n" ); document.write( "Now we divide by 0.40:
\n" ); document.write( "45/0.40 = x
\n" ); document.write( "which simplifies to:
\n" ); document.write( "112.5 = x
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