Answer:
All of the teenagers in the United States sent about 69,300,000,000 text messages each month.
Explanation:
Given that in 2019, there were about 21 million teenagers in the United States, and they each sent an average of 3,300 text messages per month, to determine about how many text messages did all of the teenagers in the United States send each month the following calculation should be done:
21,000,000 x 3,300 = X
69,300,000,000 = X
Therefore, all of the teenagers in the United States sent about 69,300,000,000 text messages each month.