Update snippet descriptions

snippets/percentile.md

@@ -3,13 +3,18 @@ title: percentile
 tags: math,intermediate
 ---
 
-Uses the percentile formula to calculate how many numbers in the given array are less or equal to the given value.
+Calculates the percentage of numbers in the given array that are less or equal to the given value.
 
 - Use `Array.prototype.reduce()` to calculate how many numbers are below the value and how many are the same value and apply the percentile formula.
 
 ```js
 const percentile = (arr, val) =>
-  (100 * arr.reduce((acc, v) => acc + (v < val ? 1 : 0) + (v === val ? 0.5 : 0), 0)) / arr.length;
+  (100 *
+    arr.reduce(
+      (acc, v) => acc + (v < val ? 1 : 0) + (v === val ? 0.5 : 0),
+      0
+    )) /
+  arr.length;
 ```
 
 ```js