Answer :
[tex]girls : x\\boys : y \\ \\ x= y+60 \\x+y=1250 \\\\substitution : \\ \\ y+60+y=1250 \\ 2y=1250-60\\2y=1190 \ \ / :2 \\ y= 595 \\ \\ x=595 +60=655 \\ \\Answer : \ there \ is \ 655 \ \ girls \ and \ 595 \ boys
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