Check whether numbers are divisible by 6 and are at least 6 (for checking the weight of a WooCommerce cart).

divisible-and-at-least-6.php

<?php

$weights = array( -6, 0, 2, 4, 6, 8, 10, 12, 13, 17, 18, 21, 24, 29, 30, 31 );

$min_weight = 6;
$increments = 6;
foreach ( $weights as $weight ) {
	echo "Weight: $weight\n";
	// Check if divisible by $increments.
	if ( $weight % $increments == 0 ) {
		echo "\tMultiple of $increments: Yes\n";
		// Verify it is at least $min_weight.
		if ( $weight / $min_weight > 0 ) {
			echo "\tAbove min weight: Yes\n";
		}
	}
	else {
		echo "\tMultiple of $increments: No\n";
	}
}

output.txt

Weight: -6
        Multiple of 6: Yes
Weight: 0
        Multiple of 6: Yes
Weight: 2
        Multiple of 6: No
Weight: 4
        Multiple of 6: No
Weight: 6
        Multiple of 6: Yes
        Above min weight: Yes
Weight: 8
        Multiple of 6: No
Weight: 10
        Multiple of 6: No
Weight: 12
        Multiple of 6: Yes
        Above min weight: Yes
Weight: 13
        Multiple of 6: No
Weight: 17
        Multiple of 6: No
Weight: 18
        Multiple of 6: Yes
        Above min weight: Yes
Weight: 21
        Multiple of 6: No
Weight: 24
        Multiple of 6: Yes
        Above min weight: Yes
Weight: 29
        Multiple of 6: No
Weight: 30
        Multiple of 6: Yes
        Above min weight: Yes
Weight: 31
        Multiple of 6: No