What is the sum of all 3 digit positive integers that can be formed using the digits 1, 4, and 8, if the digits are allowed to repeat within a number?
Answers:
A) 12,987
B) 13,876
C) 14,765
D) 15,654
E) 16,543
The number of these 3-digit numbers is   3*3*3= 
<gadget id="calculator">  3*3*3</gadget>
<output>27</output>
27   Each digit 1, 4, and 8 will appear in the ones, tens, and hundreds place 9 times each.   The sum equals 9(111) + 9(444) + 9(888)= 12,987   The answer is 12,987.
<result>A</result>
What is the sum of all 3 digit positive integers that can be formed using the digits 1, 4, and 8, if the digits are allowed to repeat within a number?