diff --git a/spec/pdf/core_decimal_rounding_spec.r b/spec/pdf/core_decimal_rounding_spec.r
deleted file mode 100644
index 3644c39..0000000
--- a/spec/pdf/core_decimal_rounding_spec.r
+++ /dev/null
@@ -1,14 +0,0 @@
-require_relative 'spec_helper'
-
-RSpec.describe PDF::Core do
-  context 'Decimal rounding' do
-    it 'rounds floating point numbers to four decimal places' do
-      expect(described_class.real(1.23456789)).to eq 1.2346
-    end
-
-    it 'is able to create a PDF parameter list of rounded decimals' do
-      expect(described_class.real_params([1, 2.34567, Math::PI]))
-        .to eq '1.0 2.3457 3.1416'
-    end
-  end
-end
diff --git a/spec/pdf/core_decimal_rounding_spec.rb b/spec/pdf/core_decimal_rounding_spec.rb
new file mode 100644
index 0000000..79e9274
--- /dev/null
+++ b/spec/pdf/core_decimal_rounding_spec.rb
@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe PDF::Core do
+  example_group 'Decimal rounding' do
+    it 'rounds floating point numbers to four decimal places' do
+      expect(described_class.real(1.23456789)).to eq '1.23457'
+    end
+
+    it 'is able to create a PDF parameter list of rounded decimals' do
+      expect(described_class.real_params([1, 2.345678, Math::PI]))
+        .to eq '1.0 2.34568 3.14159'
+    end
+  end
+end