How to Make Boxplot with a Line Connecting Mean Values in R?

# import library tidyverse
library(tidyverse)

# set seed and create a dataframe
set.seed(1068)

df <- data.frame(grp = paste0("geeks", 
                             rep(1:7, each = 56)),
                 values = c(rnorm(56, 7, 20), 
                               rnorm(56, 14, 40),
                               rnorm(56, 28, 60),
                               rnorm(56, 56, 100),
                               rnorm(56, 63, 60),
                            rnorm(56, 63, 60),
                            rnorm(56, 63, 60)))

# Get mean of data values from data frame 
mean <- df %>% 
  group_by(grp) %>% 
  summarize(average = mean(values)) %>%
  ungroup()

# Create Boxplot with a line plot using mean values
df %>% 
  ggplot(mapping = aes(x = grp, y = values)) + 
  geom_boxplot() +
  geom_line(data = mean, 
            mapping = aes(x = grp, y = average, group=1),color="green")

# import library tidyverse
library(tidyverse)

# set seed and create a dataframe
set.seed(1068)

df <- data.frame(grp = paste0("Students", 
                             rep(1:4, each = 40)),
                 values = c(rnorm(40, 100, 122), 
                               rnorm(40, 14, 21),
                               rnorm(40, 28, 93),
                               rnorm(40, 52, 100)))

# Get mean of data values from data frame 
mean <- df %>% 
  group_by(grp) %>% 
  summarize(average = mean(values)) %>%
  ungroup()

# Create Boxplot with a line plot using mean values
df %>% 
  ggplot(mapping = aes(x = grp, y = values)) + 
  geom_boxplot() +
  geom_line(data = mean,mapping = aes(x = grp, y = average, group=1),
            color="red", size=1.4)+
  coord_flip()