prices = [2, 50, 70, 30]
new_prices = []
was = []

for work in prices:
    if work <= 20:
        (new_prices.append(work * 0.20))
    elif (work >= 20) and (work >= 50):
        (new_prices.append(work * 0.40))

print(new_prices)


for price in prices:
    if price <= 20:
        price = price * 0.8
        was.append(price)
print(was)