diff --git a/calc.rb b/calc.rb
new file mode 100644
index 0000000..019fec9
--- /dev/null
+++ b/calc.rb
@@ -0,0 +1,61 @@
+#Calculator Homework
+def check_numeric_input
+  input = gets.chomp
+  check_string = /[a-zA-Z]/.match(input)
+  until check_string == nil
+    puts "\nInvalid input. Please enter a number: "
+    input = gets.chomp
+    check_string = /[a-zA-Z]/.match(input)
+  end
+  if (/[.]/.match(input) == nil)
+    #integer
+    input = input.to_i
+  else
+    #float
+    input = input.to_f
+  end
+  return input
+end
+
+# for troubleshooting method shown above
+# num = check_numeric_input
+# puts "num = #{num}"
+
+#array of valid operations
+operation_arr = %w[add + subtract - multiply * divide / exponify ** ^ modulo %]
+
+#operation user input
+puts "Please enter an operation: "
+operation = gets.chomp
+until operation_arr.include?(operation)
+  puts "\nInvalid operation. Please try again: "
+  operation = gets.chomp
+end
+
+#numeric user input
+puts "Please enter your first number: "
+num1 = check_numeric_input
+puts "Please enter your second number: "
+num2 = check_numeric_input
+while (operation == "divide" || operation == "/") && num2 == 0
+  puts "You cannot divide by zero. Please enter another value."
+  num2 = check_numeric_input
+end
+
+#calculation
+if operation == "add" || operation == "+"
+  output = num1 + num2
+elsif operation == "subtract" || operation == "-"
+  output = num1 - num2
+elsif operation == "multiply" || operation == "*"
+  output = num1 * num2
+elsif operation == "divide" || operation == "/"
+  output = num1 / num2
+elsif operation == "exponify" || operation == "**" || operation == "^"
+  output = num1 ** num2
+elsif operation == "modulo" || operation == "%"
+  output = num1 % num2
+end
+
+#Answer output
+puts "Answer: #{output}"