如何使金额增加一定数量

Question

所以我目前正在学习python，想知道如何解决这个代码问题。我试着写一个代码，你输入你想要的克数，然后它输出:它将花费多少，你将节省多少。问题是我希望当克数达到一定数量时，克数价格会下降，例如:1克是20美元，2.5克是50美元，6克是100美元，14克是180美元，28克是360美元。(两者之间的所有克数将按新的$:克数比例增加)

我试着用if语句和elif语句写一个程序，一切都很顺利，直到我添加了第三个elif语句，然后它会打印出两个elif部分或产生错误。

equation = (grams * 20)
if equation < 50:
print('That would be $', equation)
elif equation > 50:
equation = (grams * 14.2857142857)
equation_difference = (20 - 14.2857142857)
saved = (equation_difference * grams)
print('That would be $', round(equation))
print('You saved $', round(saved))
elif equation >= 180:
equation = (grams * 12.8571428571)
equation_difference = (20 - 12.8571428571)
saved = (equation_difference * grams)
print('That would be $', round(equation))
print('You saved $', round(saved))

Answer 1

第二个elif必须为

elif equation < 120:

为什么不保留克没有*20?