Question

помогите решить пожайлуста!!!

Answer 1

$left { {{x+y=50} atop {50x+100y=3500}} right. ; left { {{x=50-y} atop {x+2y=70}} right. ; left { {{x=50-y} atop {(50-y)+2y=70}} right. ; left { {{x=50-y} atop {y=20}} right. ; left { {{x=30} atop {y=20}} right.$

Детей 30, взрослых 20.

Answer 2

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