julien had 15 red candies, 7 yellow candies, and 2 blue candies. What is the ratio of blue candies to total candies? Remember to simplify your answer
The total number of candies is 15 + 7 + 2 = <<15+7+2=24>>24 candies.
Thus, the ratio of blue candies to total candies is 2:24.
Simplifying the ratio by dividing both numbers by their greatest common divisor, we get the simplified ratio as 1:12. Answer: \boxed{1:12}.