count_packets_pens = int(input())
count_packets_markers = int(input())
litres_detergent = int(input())
percentage_discount = int(input())
total_sum = count_packets_pens * 5.80 + count_packets_markers * 7.20 + litres_detergent * 1.20
discount = total_sum * (percentage_discount / 100)
sum_with_discount = total_sum - discount

print(sum_with_discount)