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Methods can also take more arguments than just `self`:

``````class DistanceConverter:
kms_in_a_mile = 1.609
def how_many_kms(self, miles):
return miles * self.kms_in_a_mile

converter = DistanceConverter()
kms_in_5_miles = converter.how_many_kms(5)
print(kms_in_5_miles)
# prints "8.045"``````

Above we defined a `DistanceConverter` class, instantiated it, and used it to convert 5 miles into kilometers. Notice again that even though `how_many_kms` takes two arguments in its definition, we only pass `miles`, because `self` is implicitly passed (and refers to the object `converter`).

### Instructions

1.

It’s March 14th (known in some places as Pi day) at Jan van High, and you’re feeling awfully festive. You decide to create a program that calculates the area of a circle.

Create a `Circle` class with class variable `pi`. Set `pi` to the approximation `3.14`.

2.

Give `Circle` an `area` method that takes two parameters: `self` and `radius`.

Return the area as given by this formula:

``area = pi * radius ** 2``
3.

Create an instance of `Circle`. Save it into the variable `circle`.

4.

You go to measure several circles you happen to find around.

• A medium pizza that is 12 inches across.
• Your teaching table which is 36 inches across.
• The Round Room auditorium, which is 11,460 inches across.

You save the areas of these three things into `pizza_area`, `teaching_table_area`, and `round_room_area`.

Remember that the `radius` of a circle is half the diameter. We gave three diameters here, so halve them before you calculate the given circle’s area.