Environmental Science 15th Edition by Scott Spoolman,Tyler Miller

Exercise 6

If you could say hello to a new person every second without taking a break and working around the clock, how many years would it take you to greet the 85 million people who were added to the world's population in 2013? (Hint: start by dividing 85 million seconds by 60 to find the number of minutes, and go from there to find the number of years.) How many years would it take for you to greet 7.1 billion people?