# 2.10: Exercises

- Page ID
- 40946

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Exercise \(\PageIndex{1}\)

Repeating my advice from the previous chapter, whenever you learn a new feature, you should try it out in interactive mode and make errors on purpose to see what goes wrong.

- We’ve seen that
`n = 42`

is legal. What about`42 = n`

? - How about
`x = y = 1`

? - In some languages every statement ends with a semi-colon,
`;`

. What happens if you put a semi-colon at the end of a Python statement? - What if you put a period at the end of a statement?
- In math notation you can multiply
`x`

and`y`

like this:`x y`

. What happens if you try that in Python?

Exercise \(\PageIndex{2}\)

Practice using the Python interpreter as a calculator:

- The volume of a sphere with radius \(r\) is \( 4/3 \pi r^3 \). What is the volume of a sphere with radius 5?
- Suppose the cover price of a book is $24.95, but bookstores get a 40% discount. Shipping costs $3 for the first copy and 75 cents for each additional copy. What is the total wholesale cost for 60 copies?
- If I leave my house at 6:52 am and run 1 mile at an easy pace (8:15 per mile), then 3 miles at tempo (7:12 per mile) and 1 mile at easy pace again, what time do I get home for breakfast?