Tính:
a) \(\displaystyle{{13} \over 3} - {7 \over 3}\) b) \(\displaystyle{5 \over 6} - {2 \over 6}\)
c) \(\displaystyle{{23} \over 7} - {{12} \over 7}\) d) \(\displaystyle{9 \over 5} - {4 \over 5}\)
a) \(\displaystyle{{13} \over 3} - {7 \over 3} = {{13 - 7} \over 3} = {6 \over 3} = 2\)
b) \(\displaystyle{5 \over 6} - {2 \over 6} = {{5 - 2} \over 6} = {3 \over 6} = {1 \over 2}\)
c) \(\displaystyle{{23} \over 7} - {{12} \over 7} = {{23 - 12} \over 7} = {{11} \over 7}\)
d) \(\displaystyle{9 \over 5} - {4 \over 5} = {{9 - 4} \over 5} = {5 \over 5} = 1\)
-- Mod Toán lớp 4