update description to match code snippet (#42856)

Author: timdeschryver

docs/csharp/linq/standard-query-operators/index.md

@@ -35,11 +35,11 @@ The standard query operators differ in the timing of their execution, depending
 
 ## Query operators
 
-In a LINQ query, the first step is to specify the data source. In a LINQ query, the `from` clause comes first in order to introduce the data source (`customers`) and the *range variable* (`cust`).
+In a LINQ query, the first step is to specify the data source. In a LINQ query, the `from` clause comes first in order to introduce the data source (`students`) and the *range variable* (`student`).
 
 :::code language="csharp" source="./snippets/standard-query-operators/IndexExamples.cs" id="ObtainDataSource":::
 
-The range variable is like the iteration variable in a `foreach` loop except that no actual iteration occurs in a query expression. When the query is executed, the range variable serves as a reference to each successive element in `customers`. Because the compiler can infer the type of `cust`, you don't have to specify it explicitly. You can introduce more range variables in a `let` clause. For more information, see [let clause](../../language-reference/keywords/let-clause.md).
+The range variable is like the iteration variable in a `foreach` loop except that no actual iteration occurs in a query expression. When the query is executed, the range variable serves as a reference to each successive element in `students`. Because the compiler can infer the type of `student`, you don't have to specify it explicitly. You can introduce more range variables in a `let` clause. For more information, see [let clause](../../language-reference/keywords/let-clause.md).
 
 > [!NOTE]
 > For non-generic data sources such as <xref:System.Collections.ArrayList>, the range variable must be explicitly typed. For more information, see [How to query an ArrayList with LINQ (C#)](../how-to-query-collections.md) and [from clause](../../language-reference/keywords/from-clause.md).