Question 226581
Let  c= # chairs(4 legs),,,,,,and  s=# stools  (3 legs)
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c+s = 40,,or c=40-s,,,number  of  seats,,,,1  seat  each  for  chair  or  stool
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4*c +3*s = 137,,,,,,,,total  number  of  legs
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subst,,,,4(40-s) +3s = 137
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160 -4s +3s =137
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160-137 = 4s-3s
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23 = s,,,,,,,,,c=40-s,,,,,c= 40-23 = 17
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check,,,,3*23 +4*17 = 69 +68 = 137,,,,ok
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