Question 1099603
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Maria + Amy    + Sadie    = 310   dollars,

M     + (M-10) + 2*(M-10) = 310  ====>


M + M - 10 + 2M - 20 = 310  ====>  4M = 340  ====>  M = {{{340/4}}} = 85.


<U>Answer</U>.  Maria pays $85,  Amy $75,  Sadie $150.
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