Question

найдите неизвестный член пропорции
х:5=21:15
12/x=8/18
4,5:0,6=x:2,4
3,4/5,1=1,4/x

Answer 1

x/5=21/15
x=5*21/15
x=7
12/x=8/18
x=12*18/8
x=27
4.5/0.6=x/2.4
x=4.5*2.4/0.6
x=18
3.4/5.1=1.4/x
x=5.1*1.4/3.4
x=2.1