<?php

$fruits = ['りんご', 'ぶどう', 'ばなな'];
$prices = [100, 150, 200, 250];
$nums = [1, 2, 3, 4, 5];

// "果物" "値段" "個数" の組み合わせ
$enums = [];

// "果物" "値段" "個数" の組み合わせを列挙
foreach ($fruits as $fruit) {
	foreach ($prices as $price) {
		foreach ($nums as $num) {
			$enums[] = [$fruit, $price, $num];
		}
	}
}

var_dump($enums);

<?php

$elems = [
	['りんご', 'ぶどう', 'ばなな'],
	[100, 150, 200, 250],
	[1, 2, 3, 4, 5],
];

// "果物" "値段" "個数" の組み合わせ
$enums = [];
$enum = [];

// "果物" "値段" "個数" の組み合わせを列挙
$dfs = function (int $idx = 0) use (&$dfs, &$enums, &$enum, $elems): void {
	if ($idx >= count($elems)) {
		$enums[] = $enum;
		return;
	}
	foreach ($elems[$idx] as $elem) {
		$enum[] = $elem;
		$dfs($idx + 1);
		array_pop($enum);
	}
};

$dfs();

var_dump($enums);