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Printsmc
algebra senior
Problem
A list of integers has mode and mean . The smallest number in the list is . The median of the list is a member of the list. If the list member were replaced by , the mean and median of the new list would be and , respectively. If were instead replaced by , the median of the new list would be . What is ?
(A)
(B)
(C)
(D)
(E)
Solution
Let there be integers on the list. The list of integers has mean , so the sum of the integers is . Replacing with will increase the sum of the list from to . The new mean of the list is , so the new sum of the list is also . Thus, we get , leading to numbers on the list. If there are numbers on the list with mode and smallest number , then the list is Since replacing with gives a new median of , and must be on the list of integers since is odd, , and the list is now The sum of the numbers on this list is , so we get: , giving answer . The original list is , with mean and median and mode . The second list is , with mean and median . The third list is with median .
Final answer
E