Question: I want to replace the missing value for male in class 2 with the median age 27.5, the missing value for female in class 2 with 40, and the missing value for male in class 3 with 26. How can I do that in R Studio?

median age for male in class 2 is 27.5

median age for female in class 2 is 40

median age for male in class 3 is 26

age <- c(34, 26, 21, NA, NA, 40, 22, 33, NA, 45) gender <- c(1, 2, 1, 1, 1, 2, 2, 1, 2, 1) # 1=male, 2=female class <- c(2, 3, 2, 2, 3, 2, 3, 1, 2, 1) df <- data.frame(age, gender, class)

	age	gender	class
1	34	1	2
2	26	1	3
3	21	1	2
4	NA	1	2
5	NA	1	3
6	40	2	2
7	22	2	3
8	33	1	1
9	NA	2	2
10	45	1	1