minor article fix

Author: kashyapm-tribe

examples/partners/model_selection_guide/model_selection_guide.ipynb

@@ -3031,7 +3031,7 @@
     "| :---- | :---- | :---- | :---- |\n",
     "| Input | 2,000 | $1.00 | $0.002 |\n",
     "| Output | 1,500 | $4.00 | $0.006 |\n",
-    "| **Total for a 1,000 pages (Stage 1\\)** |  |  | **$8.00** |\n",
+    "| **Total for 1,000 pages (Stage 1\\)** |  |  | **$8.00** |\n",
     "\n",
     "#### **Stage 2: Reasoning**\n",
     "\n",
@@ -3041,7 +3041,7 @@
     "| :---- | :---- | :---- | :---- |\n",
     "| Input | 2,000 | $0.55 | $0.0011 |\n",
     "| Output | 3,000 | $2.20 | $0.0066 |\n",
-    "| **Total for a 1,000 pages (Stage 2\\)** |  |  | **$7.70** |\n",
+    "| **Total for 1,000 pages (Stage 2\\)** |  |  | **$7.70** |\n",
     "\n",
     "#### Grand Total (per 1,000 pages): **$15.70**\n",
     "\n",