Update blob-storage-estimate-costs.md - Proposal to correct a typo and to add clarification on the calculations.

# Proposal to correct a typo and add clarification on calculations .

1. Suggestion to correct a typo:
On [this table](https://github.com/MicrosoftDocs/azure-docs/blob/main/articles/storage/blobs/blob-storage-estimate-costs.md#the-cost-to-upload), the conversion from 5 GiB to 5,120 MiB is displayed. However in the description above it, the files are mentionned to have a size of 5 MiB and not 5 GiB. I suspect that it is a typo.

2. Suggestion to add a descriptions to clarify on the calculations done in the tables

Author: gtedavid

articles/storage/blobs/blob-storage-estimate-costs.md

@@ -58,7 +58,7 @@ See [Estimate the cost of using AzCopy to transfer blobs](azcopy-cost-estimation
 
 When you upload data, your client divides that data into blocks and uploads each block individually. Each block that is upload is billed as a _write_ operation. A final write operation is needed to assemble blocks into a blob that is stored in the account. The number of write operations required to upload a blob depends on the size of each block. **8 MiB** is the default block size for uploads to the Blob Service endpoint (`blob.core.windows.net`) and that size is configurable. **4 MiB** is the block size for uploads to the Data Lake Storage endpoint (`dfs.core.windows.net`) and that size isn't configurable. A smaller block size performs better because blocks can upload in parallel. However, the cost is higher because more write operations are required to upload a blob.
 
-Using the [Sample prices](#sample-prices) that appear in this article, and assuming an **8-MiB** block size, the following table estimates the cost to upload **1000** blobs that are each **5 MiB** in size to the hot tier.
+Using the [Sample prices](#sample-prices) that appear in this article, and assuming an **8-MiB** block size, the following table estimates the cost to upload **1000** blobs that are each **5 GiB** in size to the hot tier. The calculation for the "Cost of write operations" uses the price of a single operation instead of the price for 10,000 operations on the Azure Pricing Calculator.
 
 | Price factor                                             | Value          |
 |----------------------------------------------------------|----------------|
@@ -83,9 +83,11 @@ Using the [Sample prices](#sample-prices) that appear in this article, the follo
 | Price of a single read operation (price / 10,000)    | $0.000001  |
 | **Cost of read operations (1000 * operation price)** | **$0.001** |
 | Price of data retrieval (per GiB)                    | $0.01      |
-| **Cost of data retrieval (5 * operation price)**     | **$0.05**  |
+| **Cost of data retrieval (5 * data retrieval's price per GiB)**     | **$0.05**  |
 | **Total cost (read + retrieval)**                    | **$0.051** |
 
+The calculation for the "Cost of read operations" uses the price of a single, read or write, operation instead of the price for 10,000 operations on the Azure Pricing Calculator.
+
 Utilities such as AzCopy also use list operations and operations to obtain blob properties. As a proportion of the overall bill, these charges are relatively small. For examples, see [Estimate the cost to download](azcopy-cost-estimation.md#the-cost-to-download). 
 
 #### The cost to copy between containers
@@ -102,6 +104,8 @@ Using the [Sample prices](#sample-prices) that appear in this article, the follo
 | **Cost of read operations (1,000 * operation price)** | **$0.00044** |
 | **Total cost (previous section + retrieval + read)**  | **$0.0068**  |
 
+The calculations for the 'Cost of read operations' and 'Cost of write operations' use the price of a single read or write operation instead of the price for 10,000 operations on the Azure Pricing Calculator.
+
 For a complete example, see [Estimate the cost to copy between containers](azcopy-cost-estimation.md#the-cost-to-copy-between-containers). 
 
 ## The cost to rename a blob
@@ -121,6 +125,8 @@ Using the [Sample prices](#sample-prices) that appear in this article, the follo
 | Price of a single iterative write operation to the Data Lake Storage endpoint (price / 100) | $0.000715   | $0.000715  | $0.000715  |
 | **Cost to rename Data Lake Storage directories (1000 * operation price)**                   | **$0.715**  | **$0.715** | **$0.715** |
 
+The calculations for the "Cost to rename" uses the price of a single operation instead of the price for 10,000 operations on the Azure Pricing Calculator.
+
 Based on these calculations, the cost to rename 1,000 blobs in the hot tier differs by **70** cents.
 
 ## The cost to rename a directory
@@ -138,6 +144,8 @@ Using the [Sample prices](#sample-prices) that appear in this article, the follo
 | Price of a single iterative write operation to the Data Lake Storage endpoint (price / 100) | $0.000715  | $0.000715  | $0.000715  |
 | **Cost to rename Data Lake Storage directories (1000 * operation price)**                   | **$0.715** | **$0.715** | **0.715**  |
 
+The calculations for the "Cost to rename" uses the price of a single operation instead of the price for 10,000 operations on the Azure Pricing Calculator.
+
 Based on these calculations, the cost to rename 1,000 directories in the hot tier that each contain 1,000 blobs differs by almost **$5.00**. For directories in the cold tier, the difference is over **$17**.
 
 ## Example: Upload, download, and change access tiers