- round: documentation ( source)
- print_r: documentation ( source)
- floor: documentation ( source)
<?php
$input='46.9';
$floor=floor($input);
$tens=round($input,-1);
echo $floor.' '.$tens."\n";
$array = array(
'0',
'20' => '0-20',
'50' => '20-50',
'100' => '50-100',
'200' => '100-200',
'500' => '200-500',
);
print_r($array);