Question 1017205
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A=Andrew's age; K=Kati's age=A+87yrs
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K-9=4(A-9)
(A+87)-9=4A-36
A+78=4A-36
A+114=4A
114=3A
38=A
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ANSWER; Andrew is 38 years old.
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CHECK:
K=A+87=38+87=125
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K-9=4(A-9)
125-9=4(38-9)
116=4(29)
116=116
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