<PRE><B>Question 523646</B>
Alex, Sandra, and Mary were counting their pennies. Alex and Sandra together had 31. Sandra and Mary together had 19. Alex and Mary together had 24. How may pennies did each student have? 
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Equations:
a + 0 + s = 31
0 + m + s = 19
a + m + 0 = 24
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Use any method you know to get:
a = 18
m =  6
s = 13
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Cheers,
Stan H.
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