Question 1101301
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Kathy + Bill + Sally       = 45

K      + B    + S          = 45

(B+7)  + B     + ((B+7)-5) = 45

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3B + 7 + 7 - 5 = 45


3B + 9 = 45  ====>  3B = 45 - 9 = 36  ====>  B= {{{36/3}}} = 12.


<U>Answer</U>.  Bill is 12 yeras old. Kathy is b+7 = 12+7 = 19 years,  Sally is K-5 = 19-5 = 14 years old.


<U>Check</U>.   12 + 19 + 14 = 45.   ! Correct !
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Solved.