150 : 50 * 100 + 3000 =3300
1) 150 : 50 = 3
2) 3 * 100 = 300
3) 300 + 3000 = 3300
138270 - 135*2 - 8*1000 = 130000
1) 135 * 2 = 270
2) 8 *1000 = 8000
3) 138270 - 270 = 138000
4) 138000 - 8000 = 130000
245 : 5 *8 + 10000 - 90 =10302
1) 245 : 5 = 49
2) 49 * 8 = 392
3) 392 + 10000 = 10392
4) 10392 -90 = 10302
315 : 3 * 10 + 300 + 7 =1357
1) 315 : 3 = 105
2) 105 * 10 = 1050
3) 1050 + 300 = 1350
4) 1350 + 7 = 1357