A table showing the percentages of the total population of a town by age groups for the year 2016 is given below.
| Age Group (in years) | Per cent | 
| up to 15 | 35 | 
| 16–30 | 18.5 | 
| 30–40 | 12.5 | 
| 40–50 | 25.77 | 
| 51 and above | 8.23 | 
There are 2200 billion people below 40 years. How many billion people are in the age group 40-50?