Variance

You have found the following ages (in years) of $4$ gorillas. The gorillas are randomly selected from the $20$ gorillas at your local zoo: $\qquad7,\enspace 10,\enspace 15,\enspace 21$ **Based on your sample, what is the average age of the gorillas? What is the estimated variance of the ages?** *You may round your answers to the nearest tenth.* Average age: $\quad$ [[☃ numeric-input 1]] years old Variance: $\quad$ [[☃ numeric-input 2]] years$^2$