
Answer: 45
Step-by-step explanation:
In​ 2016, 1 out of every 5 people under the age of 50 used a cell phone to read​ e-books. This means that 2 out of every 10 people under the age of 50 used a cell phone to read​ e-books. Also, 3 out of every 15 people under the age of 50 used a cell phone to read​ e-books.
Therefore, if there were x people under the age of 50 in​ 2016, then the number that used a cell phone to read​ e-books would be
1/5 Ă— x = x/5
If there were approximately 225 million people under the age of 50 in​ 2016, then the number that were likely to have read an​ e-book on a cell​ phone is
225/5 = 45 people.