1 . tính bằng hai cách
3/4 x 1/2 x 2
Cách 1 : ....................................................................................
Cách 2 : .....................................................................................
( 3/4+1/2 ) x 5/7
Cách 1 : ....................................................................................
Cách 2 : ....................................................................................
5/7 x 13/21 + 2/7 x 13/21
Cách 1 : ....................................................................................
Cách 2 : ....................................................................................
7/5 + 4/3 + 7/5 + 4/3
Cách 1 : ....................................................................................
Cách 2 : ....................................................................................
a) Cách 1
\(\frac{3}{4}\)x \(\frac{1}{2}\)x \(2\)
= \(\frac{3}{8}\)x \(2\)
= \(\frac{3}{4}\)
Cách 2
\(\frac{3}{4}\)x \(\frac{1}{2}\)x \(2\)
= \(\frac{3}{4}\)x \(\left(\frac{1}{2}x2\right)\)
= \(\frac{3}{4}\)x 1
= \(\frac{3}{4}\)