diff --git a/study/001_introduction-to-probability-statistics-and-random-processes/README.md b/study/001_introduction-to-probability-statistics-and-random-processes/README.md
index c657e6a..625b676 100644
--- a/study/001_introduction-to-probability-statistics-and-random-processes/README.md
+++ b/study/001_introduction-to-probability-statistics-and-random-processes/README.md
@@ -10,4 +10,5 @@ TODO:
 
 - ch1 end of chapter problems
 - ch2 end of chapter problems
+- 3.1.6 problems
 - ch3 end of chapter problems