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Difficulty: 2 of 5 Latest: Eight of them (in Numbers)
A 4-digit zeroless number N=ABCD has a certain specific feature:
The last 3 digits of a product ABCD*DCBA are zeros.

List all such numbers, explaining your reasoning.

(No Solution Yet, 1 Comments) Submitted on 2020-06-03 by Ady TZIDON   
Difficulty: 2 of 5 Bonus: Simple coins (in Probability) Rating: 3.88
I toss two coins and look at the outcome. I then tell you that at least one of the coins is showing up as "tails". What is the chance that the other one is showing "tails" as well?

(from techInterview.org)

(Solution Posted, 45 Comments) Submitted on 2002-04-09 by art   
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