I am confused to calculate the proprtion of certain value using mutate , however it gives a value of 1. how I can fix it?

```
x<- c(5,10,30,40,45,35)
y<- c("xrt","stu","brs","stu","ftc","xrt")
z<- c("bl","bl","xl","xl","dl","dl")
df<- data.frame(x,y,z)
library(tidyverse)
og<- df%>%group_by(y,z)%>%summarise(x=sum(x))
og<- og%>%mutate(pr = x/(sum(x)))
```

y z x pr

1 brs xl 30 1

2 ftc dl 45 1

3 stu bl 10 0.2

4 stu xl 40 0.8

5 xrt bl 5 0.125

6 xrt dl 35 0.875