I am very newbie with R. I have two table as follow (data frame)
ID running_time
1 10
1 2
2 1
2 3
2 4
And another table as
ID age
1 20
1 NA
2 30
2 NA
2 NA
I would like to extract information for age from table 2 and fullfill each column in table 1. My expected output is
ID running_time age
1 10 20
1 2 20
2 1 30
2 3 30
2 4 30
How could I do it in R? Thanks