# tPortmonetka - przejazdy

# range of positions: position() >= 100 and not(position() > 200)
# get last column
let cost_col = $x("//*[@id='dataTable']//tr[position() >= 100 and not(position() > 200)]/td[last()]/div");

# parse to float
let float_cost_col = cost_col.map(el => parseFloat(el.innerText.replace(',', '.')));

# sum
let cost_sum = float_cost_col.reduce((el1, el2) => el1 + el2, 0).toFixed(2);

# oneliner
calculate = $x("//*[@id='dataTable']//tr[position()>=13]/td[last()]/div").map(el => parseFloat(el.innerText.replace(',', '.'))).reduce((el1, el2) => el1 + el2, 0).toFixed(2)