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+# Number Mystery 1
+# Write a function called num_mystery that takes in 3 integers.
+# The function should calculate the sum of the 3 integers and
+# the difference between the largest integer and the smallest integer.
+# The function should return the product of these two integers you calculated.
+#
+# Hint: You may find it useful to use the max() and min() functions.
+#
+# Use the num_mystery function on 1, 2, 3 and print the result.
+# Use the num_mystery function on 5, 13, 7 and print the result.
+
+
+def num_mystery(first_int, second_int, third_int):
+    # calculate the sum of the 3 numbers
+    sum_of_three = first_int + second_int + third_int
+
+    # calculate the difference between the max and min
+    largest = max(first_int, second_int, third_int)
+    smallest = min(first_int, second_int, third_int)
+    difference = largest - smallest
+
+    # return the product
+    return sum_of_three * difference
+
+
+print(num_mystery(1, 2, 3))  # prints 12
+print(num_mystery(5, 13, 7))  # prints 200