# Transform to proportion and percentage in one line

My Code:

``````content_ratings = {'4+': 4433, '12+': 1155, '9+': 987, '17+': 622}
total_number_of_apps = 7197

for iteration_variable in content_ratings:
content_ratings[iteration_variable] /= total_number_of_apps * 100
``````

What I expected to happen:

Transformation of the proportions in the Dictionary to percentage in one line.
I did the calcuation with two statements seperated and it works well. But i think it should be possible to do the calculation with one line of code? Why it’s not running? I expected that the percentage will be stored in the Dictonary directly this way. Thanks What actually happened:

``````Replace this line with the output/error
```Your code doesn't seem to have the correct side-effects. Please re-check the instructions and your code.

<!--Enter other details below: -->``````

Your code is running. But the order of operations results in the incorrect outcome.

If `a = 10` and `b=100` then,

``````a /= b*100
``````

is the equivalent of -

``````a = a/(b * 100)
``````

in Python. Python evaluates the right side `b * 100` first and then evaluates the `/=` part.

So, instead of the percentage being 10, you end up getting 0.01.

You can either -

• Separate out the steps, or
• You can use the equivalent of `a = (a*100)/b`, if you want it in a single line.
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