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UKMT Grey Kangaroo, 2024

Algebra Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

Water makes up 80 per cent of fresh mushrooms. However, water makes up only 20 per cent of dried mushrooms. By what percentage does the mass of a fresh mushroom decrease during drying?

(A) $60$ (B) $70$ (C) $75$ (D) $80$ (E) $85$

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