820*(7146+12854)=16400000.
1.7146+12854=20000.
2.20000*820=16400000.
(1648276-693276):500=1910.
1.1648276-693276=955000.
2.955000:500=1910.
3000000:(702319-697319)=600.
1.702319-697319=5000.
2.3000000:5000=600.
2*3*40*50:12=100.
1.2*3=6.
2.6*40=240.
3.240*50=1200.
4.1200:12=100.
2520000:2:9:50:700:4=1.
1.2520000:2=1260000.
2.1260000:9=140000.
3.140000:50=2800.
4.2800:700=4.
5.4:4=1.
4*5*678*800:400:20:1356=1.
1.4*5=20.
2.20*678=13560.
3.13560*800=10848000.
4.10848000:400=27120.
5.27120:20=1356.
6.1356:1356=1.