Tính a) 480 mm + 120 mm 545 mm - 45 mm 840 m m: 3

a) 480 mm + 120 mm = 600 mm

545 mm – 45 mm= 500 mm

840 mm : 3 = 280 mm

c) 500 ml + 156 ml = 656 ml

1 000 ml – 500 ml= 500ml

250 ml x 3 = 750ml