diff --git a/math/math.go b/math/math.go
index 72b8887..83d6783 100644
--- a/math/math.go
+++ b/math/math.go
@@ -1,6 +1,6 @@
 package math
 
-func Sum(a, b int) int {
+func Sum(a, b float64) float64 {
 	return a + b
 }