Description:
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The bcmath commands do not seem to work for numbers smaller than 0.0001
for exmaple if you add 0.00001 and 0.00001 the result is zero.
Even setting the bcscale beforehand does not fix the issue.



Reproduce code:
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<?php
$a =bcadd(0.00011,0.00011,6);
$b =bcadd(0.00001,0.00001,6);
$c =bcsub((double)0.00001,(double)0.000005,6);
echo "1. 0.00011 + 0.00011 = $a OK\r\n";
echo "2. 0.00001 + 0.00001 = $b Wrong\r\n";
echo "3. 0.00001 - 0.000005 = $c Wrong\r\n";
?>

Expected result:
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1. 0.00011 + 0.00011 = 0.000220 
2. 0.00001 + 0.00001 = 0.00002 
3. 0.00001 - 0.000005 = 0.000005

Actual result:
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1. 0.00011 + 0.00011 = 0.000220 OK
2. 0.00001 + 0.00001 = 0.000000 Wrong
3. 0.00001 - 0.000005 = 0.000000 Wrong