When the two-digit integer MM, with equal digits, is multiplied by the one-digit integer M, the result is the three-digit integer NPM. What is the greatest possible value of NPM?
MM x M = NPM You need to know a digit(s) that, when multiplied by itself, gives a product that ends with itself.
I know of these: 1, 5, and 6 I'm not counting zero.
Of those, 6 is the largest, so I submit, for your approval, 66 x 6 = 396
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