Let the total cost of foundation contribution equal X
Person A = Half of X
Person B = An eighth of X
Therefore
PersonA + PersonB = (1/2)X + (1/8)X
(1/2) = (4/8)
(4/8)X + (1/8)X = (5/8)X
If X is the total, then
X - (5/8)X = the remaining amount
Therefore the unfunded portion = (3/8)X, three eighths of the money.
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