2.1/5=11/5
5.1/3=16/3
(х+11/5)*16/3=16
16/3х+176/15=16
176/15=11.11/15
16/3х=16-11.11/15
16/3х=4.4/15
х=(4.4/15)/(16/3)
х=4/5=0,8
Ответ: 0,8
<span>(100+60+8)*3= 504
1) 100*3= 300
2) 60*3= 180
3) 8*3=24
4) 300 + 180 + 24 = 504
(100+20+9)*6= 774
1) 100 * 6= 600
2) 20 *6= 120
3) 9*6=54
4) 600 + 120 + 54 = 774
(100+90+8)*5= 990
1) 100 * 5 = 500
2) 90 * 5 = 450
3) 8 * 5 = 40
4) 500 + 450 + 40 = 990
(100+10+3)*7 = 791
1) 100 * 7 = 700
2) 10 * 7 = 70
3) 3 * 7 = 21
4) 700 + 70 + 21 = 791</span>
Я думаю,что вот так.........
<span>-5 4/9:1,6=-49/9:16/10=-49/9*10/16=-490/144=-245/72=-3 29/72</span>