Senior citizens are the persons between the age group of either 60-74 or from 75 above.
Therefore, Number of senior citizens in the town = 80000 + 40000
= 1 lakh 20 thousand
Hence, the number of senior citizens in the town are 1 lakh 20 thousand.
On observing the given bar graph,
30-44 and 45 – 59 are the two age groups with the same population, that is 12,000 people.