48 CMM students have a meetup together. Each holds a square tile. They lay the tiles down to form a big 7 by 7 grid, with the center position empty. How many squares are there that are fully covered by tiles.
The whole numbers 8, 10, 15, 17, 21, and 28 are arranged, without repetition, in a horizontal row so that the sum of any two numbers in adjacent positions is a perfect square. Find the sum of the middle two numbers.
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A similar problem was given in Assignment 1 of Charlotte Math Meetup.
The whole numbers 3, 4, 5, 6, 12 and 13 are arranged, without repetition, in a horizontal row so that the sum of any two numbers in adjoining positions is a perfect square. Find the sum of the middle two numbers.