subset data frame based on percentage

Question

i have a data frame that contains a data like this :

V1 V2 V3
1  2  0.34
1  3  0.31
1  4  0.12
1  5  0.12

the data frame is bigger but that

Answer 1

ss <- subset(dataFrame, subset=(dataFrame$V3 <= quantile(dataFrame$V3, 0.20)))