diff --git a/exercises/conversions/from_into.rs b/exercises/conversions/from_into.rs
index 8fb9eb05..0bfe555b 100644
--- a/exercises/conversions/from_into.rs
+++ b/exercises/conversions/from_into.rs
@@ -18,7 +18,6 @@ impl Default for Person {
     }
 }
 
-// I AM NOT DONE
 // Your task is to complete this implementation
 // in order for the line `let p = Person::from("Mark,20")` to compile
 // Please note that you'll need to parse the age component into a `usize`
@@ -35,6 +34,23 @@ impl Default for Person {
 // Otherwise, then return an instantiated Person object with the results
 impl From<&str> for Person {
     fn from(s: &str) -> Person {
+        // Can be neglected as in this case the age rule will always fail
+        // if s.len() == 0 {
+        //     return Person::default();
+        // }
+        let mut splits = s.splitn(2, ',');
+        let name = splits.next().unwrap();
+        let part = splits.next().unwrap_or_default().parse::<usize>();
+        // Person can never be aged 0
+        let age = part.unwrap_or_default();
+        if  name.len() > 0 && age > 0 {
+            return Person {
+                name: String::from(name),
+                age: age
+            }           
+        } else {
+            return Person::default();
+        }
     }
 }
 
@@ -75,6 +91,7 @@ mod tests {
     fn test_bad_age() {
         // Test that "Mark.twenty" will return the default person due to an error in parsing age
         let p = Person::from("Mark,twenty");
+        println!("{:?}", p);
         assert_eq!(p.name, "John");
         assert_eq!(p.age, 30);
     }
diff --git a/exercises/conversions/using_as.rs b/exercises/conversions/using_as.rs
index 54f96515..3781c826 100644
--- a/exercises/conversions/using_as.rs
+++ b/exercises/conversions/using_as.rs
@@ -2,13 +2,12 @@
 // Please note that the `as` operator is not only used when type casting.
 // It also helps with renaming imports.
 
-// I AM NOT DONE
 // The goal is to make sure that the division does not fail to compile
 fn average(values: &[f64]) -> f64 {
     let total = values
         .iter()
         .fold(0.0, |a, b| a + b);
-    total / values.len()
+    total / (values.len() as f64)
 }
 
 fn main() {
diff --git a/exercises/threads/threads1.rs b/exercises/threads/threads1.rs
index 1785e8ce..2952930f 100644
--- a/exercises/threads/threads1.rs
+++ b/exercises/threads/threads1.rs
@@ -5,9 +5,7 @@
 // of "waiting..." and the program ends without timing out when running,
 // you've got it :)
 
-// I AM NOT DONE
-
-use std::sync::Arc;
+use std::sync::{Arc, Mutex};
 use std::thread;
 use std::time::Duration;
 
@@ -16,15 +14,19 @@ struct JobStatus {
 }
 
 fn main() {
-    let status = Arc::new(JobStatus { jobs_completed: 0 });
+    // Introduce Mutex
+    let status = Arc::new(Mutex::new(JobStatus { jobs_completed: 0 }));
     let status_shared = status.clone();
     thread::spawn(move || {
         for _ in 0..10 {
             thread::sleep(Duration::from_millis(250));
-            status_shared.jobs_completed += 1;
+            // Lock mutex and make mutable
+            let mut jobStatus = status_shared.lock().unwrap();
+            jobStatus.jobs_completed += 1;
         }
     });
-    while status.jobs_completed < 10 {
+    // Not assigning should release lock before sleep
+    while status.lock().unwrap().jobs_completed < 10 {
         println!("waiting... ");
         thread::sleep(Duration::from_millis(500));
     }