diff --git a/calculator.rb b/calculator.rb
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+# This program is a calculator!  It takes input from the user 
+# (operation & 2 numbers) and prints the calculation based on their input
+
+# Method for checking for a valid math operation
+# Allows symbol or word
+def valid_operator(operator_p)
+  until ["add", "+", "subtract", "-", "multiply", "*", "divide", "/"].include? operator_p
+    puts "\n(!) Hmm... I didn't quite understand that."
+    puts "(!) Please choose from the following operators:"
+    puts "(!) (You can enter the word or the symbol)
+    \nadd (+), subtract (-), multiply (*), divide (/)"
+    print "\nSo..what'll it be? ==> "
+    operator_p = gets.chomp.downcase
+  end
+  return operator_p
+end
+
+# Method for displaying a message recognizing the user's input
+def welcome(operator_p)
+  case operator_p
+  when "add", "+"
+    puts "Looks like you want to add!  Great choice."
+  when "subtract", "-"
+    puts "Looks like we'll be subtracting.  Fun!"
+  when "multiply", "*"
+    puts "Multiplication Station ahoy!"
+  when "divide", "/"
+    puts "Divide & conquer, eh?"
+  end
+end
+
+# Method for checking for a valid number
+# Allows only integers (no number words)
+def valid_number(num_p)
+  until num_p.to_i.to_s == num_p
+    puts "I'm not sure that's a number... try again please!"
+    puts "You can enter an integer (like 1 or 5)."
+    print "\nPlease re-enter your number ==> "
+    num_p = gets.chomp
+  end
+  return num_p.to_i
+end
+
+# Method for math calculations (a single method to rule them all)
+# Sets parameters and determines a case for the operator_p parameter
+def math(number1,number2,operator_p)
+  case operator_p
+  when "add", "+"
+    return number1 + number2
+  when "subtract", "-"
+    return number1 - number2
+  when "multiply", "*"
+    return number1 * number2
+  when "divide", "/"
+    while number2 == 0
+      puts "Hmm... we can't divide by zero... \nplease enter another non-zero number ==> "
+      number2 = gets.chomp.to_f
+    end
+    return number1.to_f / number2.to_f
+  end
+end
+
+# Welcome
+puts "\n*****************************"
+puts "Welcome to Leah's Calculator!"
+puts "*****************************"
+puts "\nLet's do some math!"
+puts "Tell me an operator and some numbers, and I'll tell you the answer."
+puts "\nHere are your choices: add (+), subtract (-), multiply (*), or divide (/)."
+
+# Read in input from user, check for input using methods
+print "\nWhat operator would you like? => "
+operator = gets.chomp.downcase
+operator = valid_operator(operator)
+puts welcome(operator)
+
+print "\nWhat's your first number? ==> "
+num1 = gets.chomp
+num1 = valid_number(num1)
+
+print "\nWhat's your second number? ==> "
+num2 = gets.chomp
+num2 = valid_number(num2)
+
+# Display answer to user
+answer = math(num1,num2,operator)
+puts "\n*************************"
+puts "Your answer is #{answer}!"
+puts "*************************"