Docs: corrected "and" --> "an"
@@ -147,7 +147,7 @@ final combined profit which will be returned in the response of the aggregation.
==== Worked Example
-Imagine a situation where you index the following documents into and index with 2 shards:
+Imagine a situation where you index the following documents into an index with 2 shards:
[source,js]
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