Posted by Emily on Monday, July 16, 2012 at 3:49pm.
1.) A security code has seven characters. Each code begins with two digits, then two letters, and finally three digits. the number of distinct security codes possible if repetition is allowed?
2.) How many ten digit phone numbers are possible if a number may not begin with a 0 or a 1?

Math  ALI, Saturday, March 5, 2016 at 3:02am
216