a)214+6*48-513:9-28*4+175:7:5=214+288-57-112+25:5=214+288-57-112+5=502-57-112+5=445-112+5=333+5=338
b)1000-104*9+36*8+413:7*6-456:3=1000-936+288+59*6-152=1000-936+288+354-152=64+288+354-152=352+354-152=706-152=554
c)12.000-36*25:3-651:7*9+736:4:8=12.000-900:3-93*9+184:8=12.000-300-837+23=11.700-837+23=10.863+23=10.886