diff --git a/solutions/system_design/mint/README.md b/solutions/system_design/mint/README.md
index 1ec31674..79080d46 100644
--- a/solutions/system_design/mint/README.md
+++ b/solutions/system_design/mint/README.md
@@ -110,7 +110,7 @@ PRIMARY KEY(id)
 FOREIGN KEY(user_id) REFERENCES users(id)
 ```
 
-We'll create an [index](https://github.com/donnemartin/system-design-primer#use-good-indices) on `id`, `user_id `, and `created_at` to speed up lookups (log-time instead of scanning the entire table) and to keep the data in memory.  Reading 1 MB sequentially from memory takes about 250 microseconds, while reading from SSD takes 4x and from disk takes 80x longer.<sup><a href=https://github.com/donnemartin/system-design-primer#latency-numbers-every-programmer-should-know>1</a></sup>
+We'll create an [index](https://github.com/donnemartin/system-design-primer#use-good-indices) on `id`, `user_id`, and `created_at` to speed up lookups (log-time instead of scanning the entire table) and to keep the data in memory.  Reading 1 MB sequentially from memory takes about 250 microseconds, while reading from SSD takes 4x and from disk takes 80x longer.<sup><a href=https://github.com/donnemartin/system-design-primer#latency-numbers-every-programmer-should-know>1</a></sup>
 
 We'll use a public [**REST API**](https://github.com/donnemartin/system-design-primer#representational-state-transfer-rest):
 
@@ -160,7 +160,7 @@ PRIMARY KEY(id)
 FOREIGN KEY(user_id) REFERENCES users(id)
 ```
 
-We'll create an [index](https://github.com/donnemartin/system-design-primer#use-good-indices) on `id`, `user_id `, and `created_at`.
+We'll create an [index](https://github.com/donnemartin/system-design-primer#use-good-indices) on `id`, `user_id`, and `created_at`.
 
 The `monthly_spending` table could have the following structure:
 
@@ -174,7 +174,7 @@ PRIMARY KEY(id)
 FOREIGN KEY(user_id) REFERENCES users(id)
 ```
 
-We'll create an [index](https://github.com/donnemartin/system-design-primer#use-good-indices) on `id` and `user_id `.
+We'll create an [index](https://github.com/donnemartin/system-design-primer#use-good-indices) on `id` and `user_id`.
 
 #### Category service
 
diff --git a/solutions/system_design/sales_rank/README.md b/solutions/system_design/sales_rank/README.md
index 71ad1c7d..a6c340ad 100644
--- a/solutions/system_design/sales_rank/README.md
+++ b/solutions/system_design/sales_rank/README.md
@@ -196,7 +196,7 @@ FOREIGN KEY(category_id) REFERENCES Categories(id)
 FOREIGN KEY(product_id) REFERENCES Products(id)
 ```
 
-We'll create an [index](https://github.com/donnemartin/system-design-primer#use-good-indices) on `id `, `category_id`, and `product_id` to speed up lookups (log-time instead of scanning the entire table) and to keep the data in memory.  Reading 1 MB sequentially from memory takes about 250 microseconds, while reading from SSD takes 4x and from disk takes 80x longer.<sup><a href=https://github.com/donnemartin/system-design-primer#latency-numbers-every-programmer-should-know>1</a></sup>
+We'll create an [index](https://github.com/donnemartin/system-design-primer#use-good-indices) on `id`, `category_id`, and `product_id` to speed up lookups (log-time instead of scanning the entire table) and to keep the data in memory.  Reading 1 MB sequentially from memory takes about 250 microseconds, while reading from SSD takes 4x and from disk takes 80x longer.<sup><a href=https://github.com/donnemartin/system-design-primer#latency-numbers-every-programmer-should-know>1</a></sup>
 
 ### Use case: User views the past week's most popular products by category