diff --git a/src/utils/helpers.ts b/src/utils/helpers.ts
index c35c637..9a64e46 100644
--- a/src/utils/helpers.ts
+++ b/src/utils/helpers.ts
@@ -3,4 +3,8 @@ export const range = (start: number, stop: number, step = 1) =>
 
 export function classNames(...classes: (string | null | undefined)[]) {
     return classes.filter(Boolean).join(" ");
+}
+
+export function sum(a: number, b: number): number {
+    return a + b;
 }
\ No newline at end of file
diff --git a/src/utils/math.ts b/src/utils/math.ts
new file mode 100644
index 0000000..98b883e
--- /dev/null
+++ b/src/utils/math.ts
@@ -0,0 +1,10 @@
+import {range, sum} from "@/utils/helpers";
+
+export function failureProbability(boxCount: number, attempts: number): number {
+    const upperRange = boxCount - attempts;
+    return range(attempts + 1, attempts + upperRange).map(n => 1.0 / n).reduce(sum);
+}
+
+export function successProbability(boxCount: number, attempts: number) {
+    return 1.0 - failureProbability(boxCount, attempts);
+}
\ No newline at end of file