Here is how you can use a loop to get input, and append the burger prices to a list:
burgerPrices = []
for n in range(3):
burgerPrice = int(input())
burgerPrices.append(burgerPrice)
cokePrice = int(input())
spritePrice = int(input())
current = [burgerPrice+cokePrice for burgerPrice in burgerPrices]+\
[burgerPrice+spritePrice for burgerPrice in burgerPrices]
print(min(current) - 50)
Or even better, a list comprehension:
burgerPrices = [int(input()) for _ in range(3)]
cokePrice = int(input())
spritePrice = int(input())
current = [burgerPrice+cokePrice for burgerPrice in burgerPrices]+\
[burgerPrice+spritePrice for burgerPrice in burgerPrices]
print(min(current) - 50)
solved How can I implement loop in this program?