Fix mathematical representation on interval (range)

docs/reference/aggregations/bucket/histogram-aggregation.asciidoc

@@ -14,7 +14,8 @@ To make this more formal, here is the rounding function that is used:
 bucket_key = Math.floor((value - offset) / interval) * interval + offset
 --------------------------------------------------
 
-The `interval` must be a positive decimal, while the `offset` must be a decimal in `[0, interval[`.
+The `interval` must be a positive decimal, while the `offset` must be a decimal in `[0, interval)`
+(a decimal greater than or euqal to `0` and less than `interval`)
 
 The following snippet "buckets" the products based on their `price` by interval of `50`:
 
@@ -64,7 +65,7 @@ And the following may be the response:
 
 ==== Minimum document count
 
-The response above show that no documents has a price that falls within the range of `[100 - 150)`. By default the
+The response above show that no documents has a price that falls within the range of `[100, 150)`. By default the
 response will fill gaps in the histogram with empty buckets. It is possible change that and request buckets with
 a higher minimum count thanks to the `min_doc_count` setting:
 
@@ -266,10 +267,10 @@ The above will sort the buckets based on the avg rating among the promoted produ
 ==== Offset
 
 By default the bucket keys start with 0 and then continue in even spaced steps of `interval`, e.g. if the interval is 10 the first buckets
-(assuming there is data inside them) will be [0 - 9], [10-19], [20-29]. The bucket boundaries can be shifted by using the `offset` option.
+(assuming there is data inside them) will be [0, 10), [10, 20), [20, 30). The bucket boundaries can be shifted by using the `offset` option.
 
-This can be best illustrated with an example. If there are 10 documents with values ranging from 5 to 14, using interval `10` will result in
-two buckets with 5 documents each. If an additional offset `5` is used, there will be only one single bucket [5-14] containing all the 10
+This can be best illustrated with an example. If there are 10 documents with integer values ranging from 5 to 14, using interval `10` will result in
+two buckets with 5 documents each. If an additional offset `5` is used, there will be only one single bucket [5, 15) containing all the 10
 documents.
 
 ==== Response Format