diff --git a/Gemfile.lock b/Gemfile.lock
new file mode 100644
index 0000000..cae865a
--- /dev/null
+++ b/Gemfile.lock
@@ -0,0 +1,30 @@
+GEM
+  remote: http://rubygems.org/
+  specs:
+    ansi (1.5.0)
+    builder (3.2.3)
+    minitest (5.10.3)
+    minitest-reporters (1.3.8)
+      ansi
+      builder
+      minitest (>= 5.0)
+      ruby-progressbar
+    minitest-skip (0.0.1)
+      minitest (~> 5.0)
+    rake (12.3.0)
+    ruby-progressbar (1.10.1)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  minitest
+  minitest-reporters
+  minitest-skip
+  rake
+
+RUBY VERSION
+   ruby 2.5.1p57
+
+BUNDLED WITH
+   1.17.3
diff --git a/lib/binary_to_decimal.rb b/lib/binary_to_decimal.rb
index 439e8c6..9a109c7 100644
--- a/lib/binary_to_decimal.rb
+++ b/lib/binary_to_decimal.rb
@@ -2,8 +2,22 @@
 # 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
+# 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
-end
+  bit = binary_array.length - 1
+  exponent = 0
+  decimal_result = 0
+
+  if binary_array.class != Array
+    raise ArgumentError
+  else
+    until bit < 0 
+      decimal_result += binary_array[bit] * (2 ** exponent)
+      bit -= 1
+      exponent += 1
+    end 
+  end
+  
+  return decimal_result
+end
\ No newline at end of file