Question 1178666
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An increase of 13.1% means the old number was multiplied by 1+0.131 = 1.131.<br>
If x is the percentage who paid no income taxes in 1999, then<br>
{{{x(1.131) = 0.38}}}
{{{x = 0.38/1.131}}}<br>
Use a calculator....<br>