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10 votes
Alan has forgotten his 4-digit PIN code.

He knows the first digit is 3, and last digit is larger than 3.
How many different sets of 4 digits could it be?

2 Answers

8 votes
the first number obviously is 3 and the next number has to be bigger so its 6 .
User Jessa
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4.6k points
3 votes
If Alan knows one already, there is 3 more left for him to possibly know
User Nighliber
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