Ryan pose la question : What is the total number of possible combinations of a nine digit number (ie., social security number) including repeating numbers? Stephen La Rocque and Penny Nom lui répond.
A student pose la question : Jack's social security number contains each of the nonzero digits exactly once. By examining the digits from left to right, he also found that 1 divides the first digit evenly, 2 divides the sum of the first two digirs evenly, 3 divides the sum of the first three digits evenly, and so on, until 9 divides the sum of all the digits evenly. What is Jack's social security number? Penny Nom lui répond.
Chris pose la question : How many different number combinations are there for the social security system? We know that there are only a certain ammount of combinations available and the current US population is at 281 million. The number system should include as many nine digit combinations as possible using the numbers 0-9 in multiple different spots. Penny Nom lui répond.
