1 2/3 + 2 3/4 + 3 1/3 + 4 1/4
Tính:
4 - 1 = 4 - 2 = 3 + 1 = 1 + 2 =
3 - 1 = 3 - 2 = 4 - 3 = 3 - 1 =
2 - 1 = 4 - 3 = 4 - 1 = 3 - 2 =
Thực hiện phép trừ rồi điền kết quả vào chỗ trống.
4 - 1 = 3 4 - 2 = 2 3 + 1 = 4 1 + 2 = 3
3 - 1 = 2 3 - 2 = 1 4 - 3 = 1 3 - 1 = 2
2 - 1 = 1 4 - 3 = 1 4 - 1 = 3 3 - 2 = 1
>, <, = ?
| 4 – 1 … 2 | 4 – 3 … 4 – 2 |
| 4 – 2 … 2 | 4 – 1 … 3 + 1 |
| 3 – 1 … 2 | 3 – 1 … 3 – 2 |
Lời giải chi tiết:
| 4 – 1 > 2 | 4 – 3 < 4 – 2 |
| 4 – 2 = 2 | 4 – 1 < 3 + 1 |
| 3 – 1 = 2 | 3 – 1 > 3 – 2 |
4-1 > 2
4-2 = 2
4-3 < 4-2
4-1 < 3+1
| 4 – 1 > 2 | 4 – 3 < 4 – 2 |
| 4 – 2 = 2 | 4 – 1 < 3 + 1 |
| 3 – 1 = 2 | 3 – 1 > 3 – 2 |
>, <, = ?
| 4 – 1 … 2 | 4 – 3 … 4 – 2 |
| 4 – 2 … 2 | 4 – 1 … 3 + 1 |
| 3 – 1 … 2 | 3 – 1 … 3 – 2 |
Lời giải chi tiết:
| 4 – 1 > 2 | 4 – 3 < 4 – 2 |
| 4 – 2 = 2 | 4 – 1 < 3 + 1 |
| 3 – 1 = 2 | 3 – 1 > 3 – 2 |
a,1/3 .(x-2/5)=3/4 b, 7/3:(x-2/3)=4/5 c,1/3.(x-2/5)=4/5 d, 2/3.(x-1/2)-1/4.(x-2/5)=7/3 e,3/7 .(x-2/3)+1/2=5/4.(x-2) f,1/2.(x-3)+1/3.(x-4)+1/4.(x-5)=1/5 g,[2/3.(x-1/2)-4/5]:(x-1/3)=21/5 h, {x-[1/2.(x-3)+11/5]}:(x-1/2)=3/5 i,x.(x-2/5)-(x+2).x+11/4=4/3
a: =>x-2/5=3/4:1/3=3/4*3=9/4
=>x=9/4+2/5=45/20+8/20=53/20
b: =>x-2/3=7/3:4/5=7/3*5/4=35/12
=>x=35/12+2/3=43/12
c: 1/3(x-2/5)=4/5
=>x-2/5=4/5*3=12/5
=>x=12/5+2/5=14/5
d: =>2/3x-1/3-1/4x+1/10=7/3
=>5/12x-7/30=7/3
=>5/12x=7/3+7/30=77/30
=>x=77/30:5/12=154/25
e: \(\Leftrightarrow x\cdot\dfrac{3}{7}-\dfrac{2}{7}+\dfrac{1}{2}-\dfrac{5}{4}x+\dfrac{5}{2}=0\)
=>\(x\cdot\dfrac{-23}{28}=\dfrac{2}{7}-3=\dfrac{-19}{7}\)
=>x=19/7:23/28=76/23
f: =>1/2x-3/2+1/3x-4/3+1/4x-5/4=1/5
=>13/12x=1/5+3/2+4/3+5/4=257/60
=>x=257/65
i: =>x^2-2/5x-x^2-2x+11/4=4/3
=>-12/5x=4/3-11/4=-17/12
=>x=17/12:12/5=85/144
>, <, =?
| 2 … 4 – 1 | 3 – 2 … 3 – 1 |
| 3 … 4 – 1 | 4 – 1 …4 – 2 |
| 4 … 4 – 1 | 4 – 1 … 3 + 0 |
Lời giải chi tiết:
| 2 < 4 – 1 | 3 – 2 < 3 – 1 |
| 3 = 4 – 1 | 4 – 1 > 4 – 2 |
| 4 > 4 – 1 | 4 – 1 = 3 + 0 |
< <
= >
câu trả lời đây
1.tính thuận tiện
a. 2/3 x 4/5 + 1/3 x 4/5
b. 2/3 x 4/5 - 1/3 x 4/5
c. 1/2 : 3/4 + 1/6 : 3/4
d. 1/2 : 3/4 - 1/6 : 3/4
a)\(\dfrac{2}{3}.\dfrac{4}{5}+\dfrac{1}{3}.\dfrac{4}{5}=\left(\dfrac{2}{3}+\dfrac{1}{3}\right).\dfrac{4}{5}=1.\dfrac{4}{5}=\dfrac{4}{5}\)
b)\(\dfrac{2}{3}.\dfrac{4}{5}-\dfrac{1}{3}.\dfrac{4}{5}=\left(\dfrac{2}{3}-\dfrac{1}{3}\right).\dfrac{4}{5}=\dfrac{1}{3}.\dfrac{4}{5}=\dfrac{4}{15}\)
a) \(\dfrac{2}{3}\times\dfrac{4}{5}+\dfrac{1}{3}\times\dfrac{4}{5}=\dfrac{4}{5}\times\left(\dfrac{2}{3}+\dfrac{1}{3}\right)=\dfrac{4}{5}\times1=\dfrac{4}{5}\)
b) \(\dfrac{2}{3}\times\dfrac{4}{5}-\dfrac{1}{3}\times\dfrac{4}{5}=\dfrac{4}{5}\times\left(\dfrac{2}{3}-\dfrac{1}{3}\right)=\dfrac{4}{5}\times\dfrac{1}{3}=\dfrac{4}{15}\)
c) \(\dfrac{1}{2}:\dfrac{3}{4}+\dfrac{1}{6}:\dfrac{3}{4}=\dfrac{1}{2}\times\dfrac{4}{3}+\dfrac{1}{6}\times\dfrac{4}{3}=\dfrac{4}{3}\times\left(\dfrac{1}{2}+\dfrac{1}{6}\right)=\dfrac{4}{3}\times\dfrac{2}{3}=\dfrac{8}{9}\)
d) \(\dfrac{1}{2}:\dfrac{3}{4}-\dfrac{1}{6}:\dfrac{3}{4}=\dfrac{1}{2}\times\dfrac{4}{3}-\dfrac{1}{6}\times\dfrac{4}{3}=\dfrac{4}{3}\left(\dfrac{1}{2}-\dfrac{1}{6}\right)=\dfrac{4}{3}\times\dfrac{1}{3}=\dfrac{4}{9}\)
c)\(\dfrac{1}{2}:\dfrac{3}{4}+\dfrac{1}{6}:\dfrac{3}{4}=\dfrac{1}{2}.\dfrac{4}{3}+\dfrac{1}{6}.\dfrac{4}{3}=\left(\dfrac{1}{2}+\dfrac{1}{6}\right).\dfrac{4}{3}=\dfrac{2}{3}.\dfrac{4}{3}=\dfrac{8}{9}\)
d)\(\dfrac{1}{2}:\dfrac{3}{4}-\dfrac{1}{6}:\dfrac{3}{4}=\dfrac{1}{2}.\dfrac{4}{3}-\dfrac{1}{6}.\dfrac{4}{3}=\left(\dfrac{1}{2}-\dfrac{1}{6}\right).\dfrac{4}{3}=\dfrac{1}{3}.\dfrac{4}{3}=\dfrac{4}{9}\)
1+1+1+1+1+1+1=?
2+2+2+2+2+2+2=?
3+3+3+3+3+3+3=?
4+4+4+4+4+4+4=?
5+5+5+5+5+5=?
Tính:
| 3 + 1 = … | 4 – 2 = … | 1 + 2 = … |
| 4 – 3 =…. | 3 – 2 =… | 3 – 1 =… |
| 4 – 1 = …. | 4 – 3 =… | 3 – 2 = …. |
Lời giải chi tiết:
| 3 + 1 = 4 | 4 – 2 = 2 | 1 + 2 = 3 |
| 4 – 3 = 1 | 3 – 2 = 1 | 3 – 1 = 2 |
| 4 – 1 = 3 | 4 – 3 = 1 | 3 – 2 = 1 |
bài 1:
1/4 + 2/3 2/7 + 2/3 2/5 + 1/3 2/3 + 1/2 1/3 + 3/5 4/5 + 1/3
1/8 + 3/4 1/36 + 5/12 1/3 + 1/6 + 1/18.
bài 2:
15/16 - 3/16 17/18 - 5/6 3/4 - 4/9 1/2 - 2/5 5/6 - 3/10 3-1/3
4/5 - 1/10 5/2 - 1 5/8 - 2/5.
Bài 1:
\(\frac14+\frac23=\frac{3}{12}+\frac{8}{12}=\frac{3+8}{12}=\frac{11}{12}\)
\(\frac27+\frac23=\frac{6}{21}+\frac{14}{21}=\frac{6+14}{21}=\frac{20}{21}\)
\(\frac25+\frac13=\frac{6}{15}+\frac{5}{15}=\frac{6+5}{15}=\frac{11}{15}\)
\(\frac23+\frac12=\frac46+\frac36=\frac{4+3}{6}=\frac76\)
\(\frac13+\frac35=\frac{5}{15}+\frac{9}{15}=\frac{5+9}{15}=\frac{14}{15}\)
\(\frac45+\frac13=\frac{12}{15}+\frac{5}{15}=\frac{12+5}{15}=\frac{17}{15}\)
\(\frac18+\frac34=\frac18+\frac68=\frac{1+6}{8}=\frac78\)
\(\frac{1}{36}+\frac{5}{12}=\frac{1}{36}+\frac{15}{36}=\frac{1+15}{36}=\frac{16}{36}=\frac49\)
\(\frac13+\frac16+\frac{1}{18}=\frac{6}{18}+\frac{3}{18}+\frac{1}{18}=\frac{6+3+1}{18}=\frac{10}{18}=\frac59\)
Bài 2:
\(\frac{15}{16}-\frac{3}{16}=\frac{15-3}{16}=\frac{12}{16}=\frac34\)
\(\frac{17}{18}-\frac56=\frac{17}{18}-\frac{15}{18}=\frac{17-15}{18}=\frac{2}{18}=\frac19\)
\(\frac34-\frac49=\frac{27}{36}-\frac{16}{36}=\frac{27-16}{36}=\frac{11}{36}\)
\(\frac12-\frac25=\frac{5}{10}-\frac{4}{10}=\frac{5-4}{10}=\frac{1}{10}\)
\(\frac56-\frac{3}{10}=\frac{25}{30}-\frac{9}{30}=\frac{25-9}{30}=\frac{16}{30}=\frac{8}{15}\)
\(3-\frac13=\frac93-\frac13=\frac{9-1}{3}=\frac83\)
\(\frac45-\frac{1}{10}=\frac{8}{10}-\frac{1}{10}=\frac{7}{10}\)
\(\frac52-1=\frac{5-2}{2}=\frac32\)
\(\frac58-\frac25=\frac{25}{40}-\frac{16}{40}=\frac{25-16}{40}=\frac{9}{40}\)
Các phân số : 1/4; 3/2; 1/3 được xếp theo thứ tự từ lớn đến bé là :
a.1/3; 3/2; 1/4;
b.3/2; 1/3; 1/4;
c.1/3; 1/4; 3/2;
d.1/4; 1/3; 3/2