The following data represent the number of people aged 25 to 64 years covered by health insurance​ (private or​ government) in 2018. Approximate the mean and standard deviation for age.
Age: 25-34 35-44 45-54 55-64
Number: 24.3 36.1 36.7 20.9
(Millions)
The mean age is:
The standard deviation is:



Answer :