diff --git a/coin.rb b/coin.rb
index 2a81365..9cec6ce 100644
--- a/coin.rb
+++ b/coin.rb
@@ -10,9 +10,19 @@ PASTA='You know what? Im done, i am leaving, we were friendly talking about the
 COIN_EMOJI = '🪙'
 BAG_EMOJI = '💰'
 
-$coin_state_active = false
+COIN_STATE_IDLE = 0
+COIN_STATE_ACTIVE = 1
+COIN_STATE_MATH = 2
+
+MATH_PROBLEM_COIN_GAIN = 3
+
+$coin_state_active = COIN_STATE_IDLE
 $coins_offered_today = 0
 
+$mathproblem_op1 = 0
+$mathproblem_op2 = 0
+$mathproblem_operator = "+"
+
 bot = Discordrb::Bot.new token: ENV['DISCORD_TOKEN']
 
 def get_seconds_to_midnight(time)
@@ -60,7 +70,7 @@ def clean_name(input)
   input.tr '@', ''
 end
 
-def get_coin(event)
+def get_coin(event, amt = 1)
   # update score
   author = event.methods.include?(:author) ? event.author : event.user
 
@@ -68,13 +78,13 @@ def get_coin(event)
     if author.bot_account?
       event.respond "Bots don't get coins!"
     end
-    $coin_state_active = false
+    $coin_state_active = COIN_STATE_IDLE
     if(rand(100) == 47)
       hyper_coin_amount = rand(100)
       coins = increment_coin(event.author.id, hyper_coin_amount)
       event.respond "What astounding luck!!! #{clean_name author.display_name}, you've just activated HYPER COIN EVENT and have received #{hyper_coin_amount} coins for a grand total of #{coins} coins!"
     else
-      coins = increment_coin(author.id)
+      coins = increment_coin(author.id, amt)
       event.respond "Nice catch, #{clean_name author.display_name}! You have #{plural('coin', coins)} now!"
     end
   else
@@ -148,17 +158,45 @@ bot.reaction_add do |event|
 
 end
 
+# math problem
+bot.message(in: Integer(ENV['BOT_CHANNEL'])) do |event|
+  next unless $coin_state_active == COIN_STATE_MATH
+
+  result = eval("$mathproblem_op1 #{$mathproblem_operator} $mathproblem_op2")
+  user_result = Integer(event.message.content) rescue false
+
+  if result == user_result
+    get_coin(event, MATH_PROBLEM_COIN_GAIN)
+  else
+    event.respond "Nice try, but you're wrong!"
+  end
+end
+
 bot.run(true)
 
 loop do
   # sleep random amount of time between 1 and 4 hours
   sleep(get_random_hours(1, 4))
-  # activate coin state
-  $coin_state_active = true
-  # send coin GIF
-  bot.send_file(ENV['BOT_CHANNEL'], File.open('./coin.gif', 'r'))
-  $coins_offered_today += 1
+  if rand(6) == 1
+    # math problem
 
+    # activate coin state
+    $coin_state_active = COIN_STATE_MATH
+
+    $mathproblem_op1 = rand(10..150)
+    $mathproblem_op2 = rand(10..150)
+    $mathproblem_operator = rand(1) == 1 ? "+" : "-"
+
+    # send the math problem
+    bot.send_message(ENV['BOT_CHANNEL'], "Solve the following for #{MATH_PROBLEM_COIN_GAIN} coins: `#{$mathproblem_op1} #{$mathproblem_operator} #{mathproblem_op2}`")
+  else
+    # activate coin state
+    $coin_state_active = COIN_STATE_ACTIVE
+    # send coin GIF
+    bot.send_file(ENV['BOT_CHANNEL'], File.open('./coin.gif', 'r'))
+  end
+
+  $coins_offered_today += 1
   # if max coins per day has reached, sleep until midnight
   if $coins_offered_today >= MAX_COINS_PER_DAY
     sleep(get_seconds_to_midnight(Time.now))