Many elementary teachers don’t understand math, and it makes them anxious

Re:Many elementary teachers don’t understand math, and it ma... by malaya_zemlya on Saturday November 30, 2019 @01:27PM (#21671389)

try performing all calculations mod 10.

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Re:Many elementary teachers don’t understand math, and it ma... by chongli on Saturday November 30, 2019 @02:00PM (#21671577)

I’m not sure how to make use of your hint.

I solved the problem for n, the largest number in the sequence of eleven, and a, the number Maria erases, by the following:

n - 11 < a < n + 1

11(n + n - 10)/2 = 2012 + a

I’m interested to know what other methods may be used to solve it (apart from brute force).

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