100см-60см=40см 9см+20см=29см 8см+41см=49см 1000см-500см=500см 50см-170см+710см=590см
3,5х+2,2х=4,56
5,7х=4,56
х=4,56:5,7
х=0,8
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1) x=8*15/30
x=4
2)x=7*5/2=17.5
3) x=25*4-10=10
4) x=2*128/64=4
5) x=18*24/3=144
1) 2 7/12 + 1,75 = 2 7/12 + 1 3/4 = 2 7/12 + 1 9/12 = 3 16/12 = 4 4/12 = 4 1/3.
2)4 1/3 : 13 = 13/3:13/1 = 13/3 * 1/13 = 1/3
3)2,5 : 3 3/4 = 2 1/2 ) 3 3/4 = 5/2 * 15/4 = 5/2 * 4/15 = 2/3
4) 1/3 + 2/3 = 3/3 = 1
2*2+15*2-4*2-7
4+30-8-7
34-8-7
24-7
17
Ответ:17х