diff --git a/exercises/04_primitive_types/primitive_types1.rs b/exercises/04_primitive_types/primitive_types1.rs
index 36633400..0adbeb14 100644
--- a/exercises/04_primitive_types/primitive_types1.rs
+++ b/exercises/04_primitive_types/primitive_types1.rs
@@ -1,9 +1,7 @@
 // primitive_types1.rs
 //
 // Fill in the rest of the line that has code missing! No hints, there's no
-// tricks, just get used to typing these :)
-
-// I AM NOT DONE
+// tricks, just get
 
 fn main() {
     // Booleans (`bool`)
@@ -13,7 +11,7 @@ fn main() {
         println!("Good morning!");
     }
 
-    let // Finish the rest of this line like the example! Or make it be false!
+    let is_evening = true; // Finish the rest of this line like the example! Or make it be false!
     if is_evening {
         println!("Good evening!");
     }
diff --git a/exercises/04_primitive_types/primitive_types2.rs b/exercises/04_primitive_types/primitive_types2.rs
index f1616ed3..e11aaddc 100644
--- a/exercises/04_primitive_types/primitive_types2.rs
+++ b/exercises/04_primitive_types/primitive_types2.rs
@@ -3,7 +3,6 @@
 // Fill in the rest of the line that has code missing! No hints, there's no
 // tricks, just get used to typing these :)
 
-// I AM NOT DONE
 
 fn main() {
     // Characters (`char`)
@@ -19,7 +18,7 @@ fn main() {
         println!("Neither alphabetic nor numeric!");
     }
 
-    let // Finish this line like the example! What's your favorite character?
+    let your_character = '#'; // Finish this line like the example! What's your favorite character?
     // Try a letter, try a number, try a special character, try a character
     // from a different language than your own, try an emoji!
     if your_character.is_alphabetic() {
diff --git a/exercises/04_primitive_types/primitive_types3.rs b/exercises/04_primitive_types/primitive_types3.rs
index 8b0de44e..cf894c8f 100644
--- a/exercises/04_primitive_types/primitive_types3.rs
+++ b/exercises/04_primitive_types/primitive_types3.rs
@@ -5,10 +5,8 @@
 // Execute `rustlings hint primitive_types3` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
-
 fn main() {
-    let a = ???
+    let a = ["here is an array"; 100];
 
     if a.len() >= 100 {
         println!("Wow, that's a big array!");
diff --git a/exercises/04_primitive_types/primitive_types4.rs b/exercises/04_primitive_types/primitive_types4.rs
index d44d8776..be863098 100644
--- a/exercises/04_primitive_types/primitive_types4.rs
+++ b/exercises/04_primitive_types/primitive_types4.rs
@@ -5,13 +5,11 @@
 // Execute `rustlings hint primitive_types4` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
-
 #[test]
 fn slice_out_of_array() {
     let a = [1, 2, 3, 4, 5];
 
-    let nice_slice = ???
+    let nice_slice = &a[1..4];
 
     assert_eq!([2, 3, 4], nice_slice)
 }
diff --git a/exercises/04_primitive_types/primitive_types5.rs b/exercises/04_primitive_types/primitive_types5.rs
index f646986e..b6a99a58 100644
--- a/exercises/04_primitive_types/primitive_types5.rs
+++ b/exercises/04_primitive_types/primitive_types5.rs
@@ -5,11 +5,10 @@
 // Execute `rustlings hint primitive_types5` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
 
 fn main() {
     let cat = ("Furry McFurson", 3.5);
-    let /* your pattern here */ = cat;
+    let (name, age) = cat;
 
     println!("{} is {} years old.", name, age);
 }
diff --git a/exercises/04_primitive_types/primitive_types6.rs b/exercises/04_primitive_types/primitive_types6.rs
index 07cc46c6..d556d085 100644
--- a/exercises/04_primitive_types/primitive_types6.rs
+++ b/exercises/04_primitive_types/primitive_types6.rs
@@ -6,13 +6,12 @@
 // Execute `rustlings hint primitive_types6` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
 
 #[test]
 fn indexing_tuple() {
     let numbers = (1, 2, 3);
     // Replace below ??? with the tuple indexing syntax.
-    let second = ???;
+    let second = numbers.1;
 
     assert_eq!(2, second,
         "This is not the 2nd number in the tuple!")
diff --git a/exercises/quiz1.rs b/exercises/quiz1.rs
index 4ee5ada7..04c58552 100644
--- a/exercises/quiz1.rs
+++ b/exercises/quiz1.rs
@@ -13,10 +13,15 @@
 //
 // No hints this time ;)
 
-// I AM NOT DONE
 
 // Put your function here!
-// fn calculate_price_of_apples {
+fn calculate_price_of_apples(apples: u32) -> u32 {
+    if apples > 40 {
+        return apples;
+    }
+
+    apples * 2
+}
 
 // Don't modify this function!
 #[test]