1. Eric is allowed to choose his own telephone number. The first digits are set 425-. He can suggest any combination of numerals for the last four digits. Unfortunately, while in first grade, Eric had a great deal of trouble writing the number 8 and has hated the number ever since. How many possible telephone numbers can he construct avoiding the number 8?
2. Trevor set out on a trip. He needs to travel a total of 4500 miles. He has just had the tires on his car replaced with some very inexpensive ones from Gray's Bargain Barn that will last exactly 3000. What is the least number of spare tires of the same variety he will need to take along to complete the trip? Explain. (Is this a trick question he'll need 4 more right? ) Thanks!
3. In Kansas many fields have circular irrigation systems. A single sprinkler is placed in the center of the field. If the sprinkler sprays water just to the four edges of the field, what percent of the field is not watered?
4. A number that is a palindrome reads the same forward and backward. 90 three-digit plaindormes adn 90 four-digit palindromes exist. How many five-digit palindromes exist?
Thanks, any help would be much appreciated!