900*(16-с)=5400 400*(х-12)=3600

Question

900*(16-с)=5400 400*(х-12)=3600

Answer 1

16-c=5400:900
16-c=6
c=16-6
c=10

x-12=3600:400
x-12=9
x=12+9
x=21

Comments

умница)))моя школа....