diff --git a/notebooks/pre-algebra/unit1.ipynb b/notebooks/pre-algebra/unit1.ipynb
index 0102e19..dd3efae 100644
--- a/notebooks/pre-algebra/unit1.ipynb
+++ b/notebooks/pre-algebra/unit1.ipynb
@@ -284,11 +284,11 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "**Write a program that finds all prime numbers of a positive integer `n` in the range `[n, end]`.**\n",
+    "**Write a program that finds all prime numbers of a positive integer `n` in the range `[start, n]`.**\n",
     "\n",
-    "- Assume that `n` and `end` are positive integers greater than or equal to 1.\n",
+    "- Assume that `start` and `n` are positive integers greater than or equal to 1.\n",
     "\n",
-    "For example for `n = 1` and `end = 20`, the output of `get_primes_in_range(1, 20)` may be:\n",
+    "For example for `start = 1` and `n = 20`, the output of `get_primes_in_range(1, 20)` may be:\n",
     "\n",
     "```\n",
     "{2, 3, 5, 7, 11, 13, 17, 19}\n",
@@ -301,9 +301,9 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "def get_primes_in_range(n: int, end: int) -> set:\n",
+    "def get_primes_in_range(start: int, n: int) -> set:\n",
     "    primes: set = set()\n",
-    "    for num in range(n, end + 1):\n",
+    "    for num in range(start, n + 1):\n",
     "        if is_prime(num):\n",
     "            primes.add(num)\n",
     "    return primes\n",