????????

<body>
<h3>6.2??????????????</h3>
<h4>??10???30?????80?????????????</h4>
<p>?????????? ?</p>
<?php
$tokuten = array(
52,29,58,98,100,91,27,51,92,85,61,90,75,14,12,95,61,90,47,12,94,7,15,14,95,61,97,59);

#?10???30?????80?????????????
$count1 = 0;
$sum1 = 0;
foreach($tokuten as $t){
if($t >= 80 || ($t >= 10 && $t <= 30)) {
echo "?10???30????80???????????\$tokuten[$sum1]???? $tokuten[$sum1] ????<br />\n";
$count1++;
}
$sum1++;
}

#?80?????????????
$count2 = 0;
$sum2 = 0;
foreach($tokuten as $t){
if($t >= 80 ) { #80???
$count2++;
}
$sum2++;
}

#?10???30?????????????
$count3 = 0;
$sum3 = 0;
foreach($tokuten as $t){
if($t >= 10 && $t <= 30 ) { #10???30???
$count3++;
}
$sum3++;
}

echo "??10???30?????80?????????????? $sum1 ???????? $count1 ? ?????<br />????????????<br /><br />\n";

echo "??80?????????????? $sum2 ???????? $count2 ? ?????<br /><br />\n";

echo "??10???30?????????????? $sum3 ???????? $count3 ? ?????<br /><br />\n";

echo "????10???30???? $count3 ? ???80???? $count2 ? ??? $count2 + $count3 ? ?????<br />\n";