Until recently, all area codes had a 0 or a 1 as the middle digit and the first digit could not be 0 or 1 and the third digit could not be 2. Complete parts (a) and (b) below (a) How many area codes were possible with this arrangement? How many telephone numbers does the current 5-digit sequence permit per area code? (The first three digits that follow the area code cannot start with 0 or 1. Assume that there are no other restrictions.) There are area codes possible. (Type a whole number.) GELD The current 5-digit sequence will permit telephone numbers. (Type a whole number.) (b) The actual number of area codes under the previous system is 136. What is the most likely reason for this discrepancy between this number and your answer in part a? O A. The actual number of area codes is different from the answer to part a because in part (a) only an estimate of the number of area codes was calculated. The actual number of possible area codes is 136. OB. The actual number of area codes is different from the answer to part a because certain area codes such as 800 and others are reserved for specific uses. OC. The actual number of area codes is different from the answer to part a because there is a shortage of area codes under this system. ...

As of April 2006, roughly 50 million .com web domain names were registered (e.g., yahoo.com). (a) How many domain names consisting of just two letters in sequence can be formed? domain names How many domain names of length two are there if digits as well as letters are permitted as characters? [Note: A character length of three or more is now mandated.] domain names (b) How many domain names are there consisting of three letters in sequence? [Note: All are currently taken.] domain names How many of this length are there if either letters or digits are permitted? domain names (c) How many domain names are there consisting of four letters in sequence? domain names How many of this length are there if either letters or digits are permitted? domain names (d) As of a certain date, 95,897 of the four-character sequences using either letters or digits had not yet been claimed. If a four-character name is randomly selected on that date, what is the probability that it is already owned? (Round…

A lock uses 3 numbers as an unlock code, each of which can be 0 to 19.  If there are no restrictions on the numbers, how many possible unlock codes are available?

Apollo Spas services 216 hot tubs. If each hot tub needs 125 mL of muriatic acid, how many liters of acid are needed for all of the hot tubs? Enter an integer or decimal number [more..] Submit Question