Rút gọn phân số (theo mẫu) :
\(\displaystyle a)\;{4 \over 8} = {{4:4} \over {8:4}} = {1 \over 2}\)
\(\displaystyle b)\;{{12} \over {18}} \)
\(\displaystyle b)\;{{12} \over {18}} \)
\(\displaystyle b)\;{{12} \over {18}} \)
a) \(\displaystyle{4 \over 8} = {{4:4} \over {8:4}} = {1 \over 2}\)
b) \(\displaystyle{{12} \over {18}} = {{12:6} \over {18:6}} = {2 \over 3}\)
c) \(\displaystyle{{15} \over {35}} = {{15:5} \over {35:5}} = {3 \over 7}\)
d) \(\displaystyle{9 \over {12}} = {{9:3} \over {12:3}} = {3 \over 4}\)
-- Mod Toán lớp 5