<?php
 $v=(0.1 + 0.7) * 10;
    echo "$v\n";
    echo (int)$v."\n";
    echo (int)"$v"."\n";
//------------------
 
$v=(1/10+7/10)*10;
echo "--------\n";
    echo "$v\n";
    echo (int)$v."\n";
    echo (int)"$v"."\n";
 
//а тут ваще трагедия от перемены мест множетелей результат меняется :)
 
$v=(1/10+7*1/10)*10;
echo "--------\n";
    echo "$v\n";
    echo (int)$v."\n";
    echo (int)"$v"."\n";
 
$v=(1/10+1/10*7)*10; 
echo "--------\n";
    echo "$v\n";
    echo (int)$v."\n";
    echo (int)"$v"."\n";
 
 

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