Question

6.10.1 Exercises Exercise 1. The demographic profile of Ecuador in 2018 is • 27.08% of the population are 0–14 years old • 18.35% are 15–24 years old • 39.59 are 25–54 years old • 7.53% are 55–64 years old • 7.45% are 65 years and older. In a random sample of 20 people, what is the probability that 2 are 65 years or older, 5 are 55–64 years old, 6 are 25–54 years old, 4 are 15–24 years old and 3 are 0–14 years old?

Answer 1

from multinomial distribution:

probability that 2 are 65 years or older, 5 are 55–64 years old, 6 are 25–54 years old, 4 are 15–24 years old and 3 are 0–14 years old

=(20!/(2!*5!*6!*4!*3!))*(0.0745)²*0.0753⁵*0.3959⁶*0.1835⁴*0.2708³ =0.000114