diff --git a/Tutorial_9_answers.R b/Tutorial_9_answers.R
new file mode 100644
index 0000000..0788d55
--- /dev/null
+++ b/Tutorial_9_answers.R
@@ -0,0 +1,31 @@
+#set working directory 
+setwd("~/Desktop/r-novice-inflammation/Biocomp_tutorial11/practice_dir")
+
+#this is my answer to this week's assignment 
+
+cov_function <- function(dir, col, nrow=50){ 
+  #dir should be a path 
+  coV <- 0
+  file_list <- list.files(dir)
+  for(i in file_list){
+    table <- read.table(file= i, header=TRUE, sep=",", stringsAsFactors = FALSE)
+    num_rows <- length(table[,col])
+    if(num_rows<nrow){
+      input <- readline(prompt=paste("Warning: File", i, "has less than 50 observations. Type Y to override. Any other key to return. "))
+      if(input!="Y"){
+        sd <- sd(table[,col])
+        mean <- mean(table[,col])
+        coV <- c(coV, sd/mean)
+        cov[-0]
+        return(coV)
+      }
+    }else{
+      sd <- sd(table[,col])
+      mean <- mean(table[,col])
+      coV <- c(coV, sd/mean)
+      coV[-0]
+      return(coV)
+    }
+  }
+}
+cov_function(dir="~/Desktop/r-novice-inflammation/Biocomp_tutorial11/practice_dir/", col=4)