1. Số
a) 3/4 kg = …. g 2/5 tấn = …kg 23/25 tạ =…kg
b) 4/5 km=….m 17/120m = …cm 32/25m =…mm
c) 3/8m2 =….cm2 12/25 m2 =…dm2 68/125km2=…m2
2.Tính
4/11 : 3/7 = ……. 16/25 : 55/66 =……………….
144/165 : 12/55 = …………. 32 : 24/17 = ……………… 68/121 : 17 = ……………….
1. Số:
a) 3/4 kg=750 g ; 2/5 tấn=400 kg ; 23/25 tạ=92 kg
b) 4/5 km=800 m ; 17/120 m=14,16 cm ; 32/25 m=1280 mm
c) 3/8 m²=3750 cm² ; 12/25 m²=48 dm² ; 68/125 km²=544000 m²
2. Tính:
4/11÷3/7=4/11×7/3=28/33
16/25÷55/66=16/25×6/5=96/125
144/165÷12/55=144/165×55/12=4
32÷24/17=32×17/24=68/3
68/121÷17=4/121
Giải thích các bước giải:
Bài 1
a)$\frac{3}{4 }$ kg= 750 g
$\frac{2}{5}$ tấn=400 kg
$\frac{23}{25}$ tạ=92 kg
b)$\frac{4}{5}$ km=800 m
$\frac{17}{20}$ m= 85 cm
$\frac{32}{25}$ m =1280 mm
c)$\frac{3}{8}$ m² = 3750 cm2
$\frac{12}{25}$ m2=48 dm2
$\frac{68}{125}$ km2=544000m2
Bài 2 Tính
$\frac{4}{11}$ : $\frac{3}{7}$ = $\frac{4}{11}$ x $\frac{7}{3}$ = $\frac{28}{33}$
$\frac{16}{25}$ : $\frac{55}{66}$ = $\frac{16}{25}$ : $\frac{5}{6}$ = $\frac{16}{25}$ . $\frac{6}{5}$ = $\frac{96}{125}$
$\frac{144}{165}$ : $\frac{12}{55}$=$\frac{144}{165}$ x $\frac{55}{12}$=$\frac{132}{33}$ =4
32 : $\frac{24}{17}$ = $\frac{32}{1}$ x $\frac{17}{24}$ = $\frac{544}{24}$
$\frac{68}{121}$ : 17=$\frac{68}{121}$ x $\frac{1}{17}$ = $\frac{4}{121}$