A recruit averages 12, 15 and 18 press-ups over three days. The average number per day is:

1. Add the three totals: 12 plus 15 plus 18 gives 45. 2. Divide that total by the three days. 3. 45 divided by 3 is 15 press-ups per day. _Source: OpenStax Prealgebra 2e, Chapter 5, Decimals._