Question

You are at a bank to setup a bank account with an ATM card. The bank requires you to enter a 4-digit PIN, and each digit can be 0, 1, 2,... 9. Use this information and answer questions 3a and 3b

Answer 1

3b) not permitted sequence =N(all identical)+N(ascending )+N(descending)+N(starting with 19)+N(starting with 20)

=10+7+7+100+100 =224