Question:easy
A number lock consists of 3 rings each marked with 10 different numbers. In how many cases the lock cannot be opened?
A number lock consists of 3 rings each marked with 10 different numbers. In how many cases the lock cannot be opened?
Show Hint
Find the total number of settings of the 3 rings, then subtract the single setting that is the correct code.
Updated On: Jul 14, 2026
- 3^10
- 10^3
- 30
- 999
Show Solution
The Correct Option is D
Solution and Explanation
10^3=1000 total settings; only 1 is correct; 1000-1=999 fail.
Final Answer: 999, option (4).
Final Answer: 999, option (4).
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