See image — AITS & Test Series Chemistry Question

💡 Solution & Explanation

If the sum of digits in a number is divisible by 9, then number itself is divisible by 9  either number comprises {1, 2, 4, 5, 6} or {1, 2, 3, 5, 7}.  required probability = 7 5 2 5! 2 x 2 y 10x