diff --git a/lib/binary_to_decimal.rb b/lib/binary_to_decimal.rb
index 439e8c6..126139f 100644
--- a/lib/binary_to_decimal.rb
+++ b/lib/binary_to_decimal.rb
@@ -4,6 +4,19 @@
 # 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
+  total = 0
+  index = 0
+  size = binary_array.length
+  bit_value = size - 1
+
+  size.times do
+    element = binary_array[index]
+    total += element * (2**bit_value)
+    bit_value -= 1
+    index+=1
+  end
+  #convert to float (decimal) type.
+  return total.to_f
 end