Python Lists and For Loops Retreving multiple list elements

https://app.dataquest.io/m/312/lists-and-for-loops/4/retrieving-multiple-list-elements

I had to look up the answer. I couldn’t understand where the 2’s came from.

avg_rating = (fb_rating_data[2] + insta_rating_data[2] +
pandora_rating_data[2]) / 3

Thank you.

row_1 = ['Facebook', 0.0, 'USD', 2974676, 3.5]
row_2 = ['Instagram', 0.0, 'USD', 2161558, 4.5]
row_3 = ['Clash of Clans', 0.0, 'USD', 2130805, 4.5]
row_4 = ['Temple Run', 0.0, 'USD', 1724546, 4.5]
row_5 = ['Pandora - Music & Radio', 0.0, 'USD', 1126879, 4.0]

fb_rating_data = [row_1[0], row_1[3], row_1[-1]]
insta_rating_data = [row_2[0], row_2[3], row_2[4]]
pandora_rating_data = [row_5[0], row_5[3], row_5[4]]

avg_rating = (fb_rating_data[2] + insta_rating_data[2] + pandora_rating_data[2]) / 3

fb_rating_data contains all the numeric values. That is, fb_rating_data = [0.0, 2974676, 3,5]

insta_rating_data contains all the numeric values. That is, insta_rating_data = [0.0, 2161558, 4,5]

Since we are only interested in the third numeric value, the 2 is used to access the third element where 0 indicates the first element, 1 indicates the second element and 2 indicates the third element.

avg_rating = (fb_rating_data[2] + insta_rating_data[2] + pandora_rating_data[2]) / 3

fb_rating_data[2] contains 3.5.
insta_rating_data[2] contains 4.5.

I understand now thank you so much.