easy Probability
A release-checked easy problem for training Combinations and Permutations.
We say a non-negative integer is "almost square" if it is not a perfect square, but all of its digits are perfect squares. For example, both $149$ and $904$ are almost square, but $144$ and $936$ are not. Find the number of positive integers less than $1000$ that are almost square.
This Probability problem is tagged Combinations and Permutations. State the random variables and conditioning information explicitly, then check the result against boundary cases before opening hints or a solution.
Probability · Akuna
Probability
Probability · SIG, DE Shaw
Probability · SIG, Jane Street
Probability · Jane Street
Probability