Tính: (a) 20 cm + 18 cm = ………… (b) 43 cm + 6 cm + 30 cm = ………… (c) 56 – 22 + 10 = …………… (d) 90 – 50 – 40 = ……………
Giải thích
a) 20 cm + 18 cm = 38 cm
b) 43 cm + 6 cm + 30 cm = 79 cm
c) 56 – 22 + 10 = 44
d) 90 – 50 – 40 = 0
a) 20 cm + 18 cm = 38 cm
b) 43 cm + 6 cm + 30 cm = 79 cm
c) 56 – 22 + 10 = 44
d) 90 – 50 – 40 = 0