dd

fruit = input()
day = input()
quantity = float(input())
price = 0
if day == 'Monday' or day == 'Tuesday' or day == 'Wednesday' or day == 'Thursday' or day == 'Friday':
    if fruit == 'banana':
        print(f'{quantity * 2.50:.2f}')
    elif fruit == 'apple':
        print(f'{quantity * 1.20:.2f}')
    elif fruit == 'orange':
        print(f'{quantity * 0.85:.2f}')
    elif fruit == 'grapefruit':
        print(f'{quantity * 1.45:.2f}')
    elif fruit == 'kiwi':
        print(f'{quantity * 2.70:.2f}')
    elif fruit == 'pineapple':
        print(f'{quantity * 5.50:.2f}')
    elif fruit == 'grapes':
        print(f'{quantity * 3.85:.2f}')
    else:
        print('error')

elif day == 'Saturday' or day == 'Sunday':
    if fruit == 'banana':
        print(f'{quantity * 2.70:.2f}')
    elif fruit == 'apple':
        print(f'{quantity * 1.25:.2f}')
    elif fruit == 'orange':
        print(f'{quantity * 0.90:.2f}')
    elif fruit == 'grapefruit':
        print(f'{quantity * 1.60:.2f}')
    elif fruit == 'kiwi':
        print(f'{quantity * 3:.2f}')
    elif fruit == 'pineapple':
        print(f'{quantity * 5.60:.2f}')
    elif fruit == 'grapes':
        print(f'{quantity * 4.20:.2f}')
    else:
        print('error')

else:
    print('error')