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

for i in content_ratings:
    proportions = content_ratings[i] / total_number_of_apps
    percentages = proportions * 100

    c_ratings_proportions[i] = proportions
    c_ratings_percentages[i] = percentages
print(c_ratings_percentages)