Bar plot for 2 variables

Question

I have 2 variables

price for white cars has length 106 and price for black cars has length 71

I need to do bar plot with xlap="white","black" , ylab="mean of price" like this bar

Answer 1

How about this:

dat <- data.frame(
  color = rep(c("white", "black"), c(106, 71)), 
  price = rnorm(177, 20, 5)
  
)

ag <- aggregate(dat$price, list(dat$color), mean)
ag
#>   Group.1        x
#> 1   black 19.89868
#> 2   white 20.60027

barplot(ag$x, names.arg=ag$Group.1, ylim=c(0, max(ag$x)*1.075), col=c("gray25", "white"))
text(c(.7, 1.9), ag$x+1, round(ag$x, 1))

^{Created on 2022-04-22 by the reprex package (v2.0.1)}