Proportional segments with bracketed group sums
Rows of lettered lengths whose totals are gathered as 60, 30, 15
The folio ranks four rows of lettered line-segments by length: g = 24, h = 20, K = 16 across the top; then a = 12, c = 10, e = 8; b = 6, d = 5, f = 4; and L = 18, m = 15, n = 12. Bracketed numbers gather the group totals - 30 for the a-c-e row and 15 for the b-d-f row - while 60 (the sum of the top row) and 30 stand as column totals below. The arrangement studies how segments in the same ratio add to whole-number sums, in pencil reworked in pen.
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Ranked segments and their bracketed sums
Segments g, h, K measure 24, 20, 16 and total 60; a, c, e measure 12, 10, 8 and are bracketed as 30; b, d, f measure 6, 5, 4 and are bracketed as 15. Each lower row halves the one above it, so the same 6:5:4 ratio recurs at descending scales while the sums stay whole.