Update readme.md

Author: javadev

src/main/kotlin/g1201_1300/s1251_average_selling_price/readme.md

@@ -68,4 +68,10 @@ UnitsSold table:
     | 2          | 16.96         | 
     +------------+---------------+
 
-**Explanation:** Average selling price = Total Price of Product / Number of products sold. Average selling price for product 1 = ((100 * 5) + (15 * 20)) / 115 = 6.96 Average selling price for product 2 = ((200 * 15) + (30 * 30)) / 230 = 16.96 
+**Explanation:**
+
+Average selling price = Total Price of Product / Number of products sold.
+
+Average selling price for product 1 = ((100 * 5) + (15 * 20)) / 115 = 6.96
+
+Average selling price for product 2 = ((200 * 15) + (30 * 30)) / 230 = 16.96