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exercises/practice/robot-simulator/.docs/instructions.append.md

@@ -1,3 +1,3 @@
 ## Hint
 
-For this exercise you will need to implement a simple S3 class via its constrctor, generic method and dispatch to class method. If you are not familiar with S3, a great starting point is the [chapter on S3](http://adv-r.hadley.nz/s3.html) in Hadley Wickham's book Advanced R.
+For this exercise you will need to implement a simple S3 class via its constructor, generic method and dispatch to class method. If you are not familiar with S3, a great starting point is the [chapter on S3](http://adv-r.hadley.nz/s3.html) in Hadley Wickham's book Advanced R.