functions.php

<?php
/**
 * Custom simple product price format.
 *
 * Adds credit cart parcels in price html.
 *
 * @param  string $price Old price format.
 *
 * @return string        Price format with credit card parcels.
 */
function cs_custom_simple_product_price_html( $price ) {
    global $product;

    $parcels = 10; // Edit the number of parcels here!
    $parcel_price = $product->get_price() / 10;

    $html = '<span class="parcels">' . $parcels . 'x </span>';
    $html .= woocommerce_price( $parcel_price ) . '<br />';
    $html .= '<span class="without-interest">' . __( 'sem juros' ) . '</span><br />';
    $html .= woocommerce_price( $product->get_price() );

    return $html;
}

add_filter( 'woocommerce_price_html', 'cs_custom_simple_product_price_html' );