diff --git a/lib/binary_to_decimal.rb b/lib/binary_to_decimal.rb
index 439e8c6..8415422 100644
--- a/lib/binary_to_decimal.rb
+++ b/lib/binary_to_decimal.rb
@@ -1,9 +1,9 @@
-# A method named `binary_to_decimal` that receives as input an array of size 8.
-# The array is randomly filled with 0’s and 1’s.
-# The most significant bit is at index 0.
-# The least significant bit is at index 7.
-# Calculate  and return the decimal value for this binary number using
-# the algorithm you devised in class.
 def binary_to_decimal(binary_array)
-  raise NotImplementedError
+  index = -1
+  decimal = 0
+  (binary_array.length).times do |i|
+    decimal += binary_array[index] * (2 ** i)
+    index -= 1
+  end
+  return decimal
 end