[Question]: Missy watches 5 28-minute reality shows and one 10-minute cartoon. How long does she spend watching TV?
[Answer]: First find the total time Missy spends watching reality shows: 5 shows * 28 minutes / show = 140 minutes. Then add that amount to the time she spends watching the cartoon: 140 minutes + 10 minutes = 150 minutes.
So the answer is 150.

[Question]: My brother and I have thirty minutes to go to school, without being late. It takes us 15 minutes to arrive at the school gate, and another 6 minutes to get to the school building. How much time do we have to get to our room, without being late?
[Answer]: The total time we spent going to school is 15 minutes + 6 minutes = 21 minutes. We have 30 minutes - 21 minutes = 9 minutes left not to be late.
So the answer is 9.

[Question]: Alina and her best friend Lucia like to chat a lot. On a particular day, Alina sent 20 fewer messages than her friend Lucia, who sent 120 messages. The next day, Lucia sent 1/3 of the messages she sent the previous day, while Alina doubled the messages she sent on the first day. If they sent the same number of messages on the third day as the first day, what is the total number of messages they sent in those three days?
[Answer]:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
On the first day, Alina sent 120 - 20 = 100 messages. The total number for the first day is 100 + 120 = 220 messages. On the second day, Lucia sent 1 / 3 * 120 = 40 messages. Alina sent 100 * 2 = 200 messages on the second day. The total for the second day is 40 + 200 = 240 messages. For the three days, they sent 220 + 220 + 240 = 680 messages.
So the answer is 680.