1) 245*7 = 1715
2) 348*13 = 1044 + 348 = 4524
3) 283*703 = 849 + 1981 = 198949
A) (7 1/2*2 2/3-12 1/4:7/2):110*3/5 + (3 3/8+2 3/4):24:2 2/5=69/80
1. 7 1/2*2 2/3=15/2*8/3=15*8/2*3=5*4/1*1=20
2. 12 1/4:7/2=49/4:7/2=49*2/4*7=7*1/2*1=7/2=3,5
3. 20-3,5= 16,5
4. 110*3/5=22*3/1=66
5. 16,5:66=165/10:66=165/10*66=33/2*66=1/2*2=1/4
6. 3 3/8+2 3/4=27/8+11/4=27/8+22/8=49/8
7. 24:2 2/5=24:12/5=24*5/12=2*5=10
8. 49/8:10=49/8*10=49/80
9. 1/4+49/80=20/80+49/80=69/80
б) (3 1/4+2 1/6): 2 3/5-2/3*2 1/4+5 1/6=5 3/4=5,75
1. 3 1/4+2 1/6=13/4+13/6=3*13/12+2*13/6=39/12+26/12= 65/12
2. 65/12:2 3/5=65/12:13/5=65*5/12*13=5*5/12*1=25/12
3. 2/3*2 1/4=2/3*9/4=2*9/3*4=1*3/1*2=3/2
4. 25/12-3/2=25/12-18/12=7/12
5. 7/12+5 1/6=7/12+31/6=7/12+62/12=69/12=23/4=5 3/4
в) (4 2/5+1 1/7)*(2 8/13+3 2/3)/(144-256)=-97/312
1. 4 2/5+1 1/7=22/5+8/7=154/35+40/35=194/35
2. 2 8/13+3 2/3=34/13+11/3=102/39+143/39=245/39
3. 194/35*245/39=194*245/35*39=194*7/1*39=1358/39
4. 144-256=-112
5. 1358/39:(-112)=-1358/39*112=-97/39*8=-97/312
г) (5 9/11:1 2/9 -7 2/3*1 1/23)/(11/54-5/36)=-49 119/121
1. 5 9/11: 1 2/9=64/11:11/9=64*9/11*11=576/121
2. 7 2/3*1 1/23=23/3*24/23=23*24/3*23=24/3=8
3. 576/121-8=576/121-968/121=-392/121
4. 11/54-5/36=22/108-15/108=7/108
5. -392/121:7/108=-392*108/121*7= -56*108/121*1=-6048/121=-49 119/121
<span>−18−1,7y=46,8+3,7y
-1,7y-3,7y=18+46,8
-5,4y=64,8
y=-12
</span><span>8⋅(3+y)−4y=5y−67
24+8y-4y=5y-67
4y-5y=-24-67
-y=-91
y=91</span>
