Răspuns:
a)
3254+2000+1117=5254+1117=6371
b)
1391+1609+2472=3000+2472=5472
4000+2693+1272=6693+1272=7965
5200+2800+4516=8000+4516=12516
2570+2430+2800=5000+2800=7800
6300+1700+1300=8000+1300=9300
c)
1625+1375+3007=3000+3007=6007
3009+1001+2005=4010+2005=6015
4320+1220+1500=5540+1500=7040