protected function mul($left, $right, $precision)
    {
        if (is_null($precision)) return $left * $right;
        return floatval(\bcmul($left, $right, $precision));
    }
protected function mul($left, $right, $precision)
    {
        if (is_null($precision)) return $left * $right;
        return floatval(\bcmul($left, $right, $precision));
    }
protected function mul ( $ left , $ right , $ precision ) { if ( is_null ( $ precision ) ) return $ left * $ right ; return floatval ( \ bcmul ( $ left , $ right , $ precision ) ) ; }
Use bcmul if precision is specified
otherwise use native multiplication operator

@param $left
@param $right
@param $precision
@return float
Use bcmul if precision is specified otherwise use native multiplication operator