The age of the father is 57 years old
Calculating mean of a population
Total age = Average age x Population
Average of the four children = 15
Population = 4
Total age of the four children = 15 x 4
Total age of the four children = 60 years
If the parents are added:
Population = 6
Average age = 25
Total age = 25 x 6
Total age = 150 years
Total age of the parents = 150 - 60
Total age of the parents = 110 years
The father is 4 years older than his wife
Let the age of the father be x
The age of the wife = x - 4
x + x - 4 = 110
2x = 114
x = 114/2
x = 57
Therefore, the age of the father is 57 years old
Learn more on The mean of numbers here: https://brainly.com/question/20118982
#SPJ1
