diff --git a/hands_on/numerical_fuzzing/test_something.py b/hands_on/numerical_fuzzing/test_something.py
new file mode 100644
index 0000000..ce7bf2a
--- /dev/null
+++ b/hands_on/numerical_fuzzing/test_something.py
@@ -0,0 +1,17 @@
+import numpy as np
+from math import isclose
+
+def test_var_determistic():
+    arr = np.array([1,2,3,4,3,2,1])
+    expected = 1.0612244897959184
+    result = np.var(arr)
+    assert isclose(result, expected)
+
+def test_var_fuzzing():
+
+    size = 100000
+    variance = 1.5
+    arr = np.random.normal(size = size, scale = np.sqrt(variance))
+    expected = 1.5
+    result = np.var(arr)
+    assert isclose(result, expected, abs_tol =0.1)