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More number pyramids
When number pyramids have a sequence on the bottom layer, some interesting patterns emerge...
When number pyramids have a sequence on the bottom layer, some interesting patterns emerge...
Choose four different digits from 1-9 and put one in each box so that the resulting four two-digit numbers add to a total of 100.
Nine squares with side lengths 1, 4, 7, 8, 9, 10, 14, 15, and 18 cm can be fitted together to form a rectangle. What are the dimensions of the rectangle?