Price changes with quantity

Hi @jeanp

Please add the below snippet (How to add custom code?) and let me know if it works or not.

add_action( 'wp_enqueue_scripts', 'woopq_add_localize', 99 );
function woopq_add_localize() {
	wp_localize_script( 'woopq-frontend', 'woopq_vars', array(
			'price_format'             => get_woocommerce_price_format(),
			'price_decimals'           => wc_get_price_decimals(),
			'price_thousand_separator' => wc_get_price_thousand_separator(),
			'price_decimal_separator'  => wc_get_price_decimal_separator(),
			'currency_symbol'          => get_woocommerce_currency_symbol()
		)
	);
}

add_action( 'wp_footer', 'woopq_change_price_js', 99 );
function woopq_change_price_js() {
	?>
    <script type="text/javascript">
      jQuery(document).on('change', 'form.cart .qty', function() {
        var $this = jQuery(this);
        var $this_product = $this.closest('.product');
        var $this_price = $this_product.find('.summary .price');
        var qty = parseFloat($this.val());

        if ($this_product.attr('data-price') === undefined) {

          if ($this_price.find('ins').length) {
            var regular_price = parseFloat($this_price.find('del').text().replace(',', '.').replace(/[^0-9.]/g, ''));
            var price = parseFloat($this_price.find('ins').text().replace(',', '.').replace(/[^0-9.]/g, ''));
          } else {
            var regular_price = 0;
            var price = parseFloat($this_price.text().replace(',', '.').replace(/[^0-9.]/g, ''));
          }

          $this_product.attr('data-price', price);
          $this_product.attr('data-price-regular', regular_price);
        } else {
          var price = parseFloat($this_product.attr('data-price'));
          var regular_price = parseFloat($this_product.attr('data-price-regular'));
        }

        if ((qty > 0) && (price > 0)) {
          if (regular_price > 0) {
            $this_price.find('del').html(
                woopq_format_money(qty * regular_price, woopq_vars.price_decimals, woopq_vars.currency_symbol,
                    woopq_vars.price_thousand_separator,
                    woopq_vars.price_decimal_separator));
            $this_price.find('ins').html(
                woopq_format_money(qty * price, woopq_vars.price_decimals, woopq_vars.currency_symbol,
                    woopq_vars.price_thousand_separator,
                    woopq_vars.price_decimal_separator));
          } else {
            $this_price.html(
                woopq_format_money(qty * price, woopq_vars.price_decimals, woopq_vars.currency_symbol,
                    woopq_vars.price_thousand_separator,
                    woopq_vars.price_decimal_separator));
          }
        }
      });

      function woopq_format_money(number, places, symbol, thousand, decimal) {
        number = number || 0;
        places = !isNaN(places = Math.abs(places)) ? places : 2;
        symbol = symbol !== undefined ? symbol : '$';
        thousand = thousand || ',';
        decimal = decimal || '.';

        var negative = number < 0 ? '-' : '',
            i = parseInt(number = Math.abs(+number || 0).toFixed(places), 10) + '',
            j = 0;

        if (i.length > 3) {
          j = i.length % 3;
        }

        return symbol + negative + (
            j ? i.substr(0, j) + thousand : ''
        ) + i.substr(j).replace(/(\d{3})(?=\d)/g, '$1' + thousand) + (
            places ? decimal + Math.abs(number - i).toFixed(places).slice(2) : ''
        );
      }
    </script>
	<?php
}