Bài 1:
a) $\frac{28}{36}$ = $\frac{28:4}{36:4}$ = $\frac{7}{9}$
b) $\frac{-63}{90}$ = $\frac{-63:9}{90:9}$ =$\frac{-7}{10}$
c) $\frac{-40}{120}$ = $\frac{-40:40}{120:40}$ = $\frac{-1}{3}$
Bài 2:
a) $\frac{2.4}{6.18}$ = $\frac{8}{108}$ = $\frac{8:4}{108:4}$ = $\frac{2}{27}$
b) $\frac{3.5.7}{6.9.14}$ = $\frac{105}{756}$ = $\frac{105:21}{756:21}$ = $\frac{5}{36}$
c) $\frac{4.7-4.5}{64}$ = $\frac{8}{64}$ = $\frac{8:8}{64:8}$ = $\frac{1}{8}$
CHO MK CTLHN ĐỂ CÓ THÊM ĐỘNG LỰC
#NOCOPY
