<span>-(9+а) - (15-а)=-9-а-15+а=-24</span>
7*10=70
54*10=540
48*10=480
79*10=790
96*10=960
63*10=630
70/7=10
70/10=7
540/54=10
540/10=54
480/48=10
480/10=48
790/79=10
790/10=79
960/96=10
960/10=96
630/63=10
630/10=63
1)11,2:9.1/3=11.1/5:9.1/3=56/5:28/3=56/5×3/28=2×3/5×1=6/5=1.1/5
2)3.2/3-1.1/5=2.10-3/15=2.7/15