Hỗn số

>;<;=?

a) 15ha 3dam>1530dam2

3km2 9ha=309ha

90150m2<9ha15m2

b)5 và 12/100ha=5ha12dam2

32km2  4ha=32 và 4/10km2

\(a,4\dfrac{1}{4}-2=\dfrac{17}{4}-2=\dfrac{9}{4};\dfrac{5}{8}+2\dfrac{3}{5}=\dfrac{5}{8}+\dfrac{13}{5}=\dfrac{129}{40}\\ b,4\dfrac{4}{9}:2=\dfrac{40}{9}\cdot\dfrac{1}{2}=\dfrac{20}{9};\dfrac{2}{3}+3\dfrac{1}{6}=\dfrac{2}{3}+\dfrac{19}{6}=\dfrac{23}{6}\\ c,3\dfrac{1}{5}+2=\dfrac{9}{5}+2=\dfrac{19}{5};\dfrac{3}{5}-2\dfrac{4}{5}=\dfrac{3}{5}-\dfrac{14}{5}=-\dfrac{11}{5}\)

\(d,5\dfrac{1}{7}-2=\dfrac{36}{7}-2=\dfrac{22}{7};\dfrac{4}{5}:1\dfrac{1}{5}=\dfrac{4}{5}:\dfrac{6}{5}=\dfrac{2}{3}\\ e,2\dfrac{3}{5}+1=\dfrac{13}{5}+1=\dfrac{18}{5};\dfrac{1}{4}\cdot2\dfrac{2}{3}=\dfrac{1}{4}\cdot\dfrac{8}{3}=\dfrac{2}{3}\\ f,4\dfrac{1}{3}\cdot1=\dfrac{13}{3};\dfrac{1}{2}+5\dfrac{2}{7}=\dfrac{1}{2}+\dfrac{37}{7}=\dfrac{81}{14}\)

`3,5 = 35/10 = 30/10 + 5/10 = 3 + 5/10 = 3 5/10`

`6,33 = 633/100 = 600/100 + 33/100 = 6+33/100=6 33/100`

`18,05 = 1805/100 = 1800/100 + 5/100 = 18+5/100=18 5/100`

`217,908 = 217908/1000 = 217000/1000 + 908/1000 = 217 + 908/1000 = 217 908/1000`

3,5 \(=3\dfrac{5}{10}\)

6,33 \(=6\dfrac{33}{100}\)

18,05 \(=18\dfrac{5}{100}\)

217,908 \(=217\dfrac{908}{1000}\)

`a) 35/9 > 27/9 (vì : 35>27)`

`b) 54/10 < 52/5 = 104/10 (vì : 104 > 54)`

`c)31/2 = 155/10 > 13/5 = 26/10 (vì : 155 > 26)`

`d) 41/8 <33/4 = 66/8 (vì : 41<66)`

M = 15 
-> 15 . 40 = 600

600

15x40=600

x+\(3\dfrac{1}{5}\)=4

x=4-\(3\dfrac{1}{5}\)

x=\(\dfrac{4}{5}\)

\(x+3\dfrac{1}{5}=4\)

\(x+\dfrac{16}{5}=4\)

          \(x=4-\dfrac{16}{5}\)

          \(x=\dfrac{4}{5}\)

a, \(x+\dfrac{16}{5}=4\)

\(x=4-\dfrac{16}{5}\)

\(\Rightarrow x=\dfrac{4}{5}\)

\(40.\)

\(a\)) \(S\)

\(b\)) Đ

\(c\)) Đ

\(d\)) \(S\)

\(41.\)

\(a\)) \(1\dfrac{1}{3}+2\dfrac{1}{2}=\dfrac{4}{3}+\dfrac{5}{2}=\dfrac{23}{6}\)

\(b\)) \(3\dfrac{2}{5}-1\dfrac{1}{10}=\dfrac{17}{5}-\dfrac{11}{10}=\dfrac{23}{10}\)

\(c\)) \(3\dfrac{1}{2}.1\dfrac{1}{7}=\dfrac{7}{2}.\dfrac{8}{7}=\dfrac{56}{14}=4\)

\(d\)) \(4\dfrac{1}{6}:2\dfrac{1}{3}=\dfrac{25}{6}:\dfrac{7}{3}=\dfrac{25}{14}\)

a)83/12

b)255/14

Đáp án:

a) \(\dfrac{83}{12}\)

b) \(\dfrac{255}{14}\)

Hok tốt

\(\dfrac{3}{4}+1\dfrac{5}{6}=\dfrac{3}{4}+\dfrac{11}{6}=\dfrac{9}{12}+\dfrac{22}{12}=\dfrac{31}{12}\)

=3/4+11/6=31/12

3/4 + 11/6= 31/12