8/9 - 2/6 + 5/12=
5/12 + 3/4 + 1/3=
1/12 + 5/6 + 3/8=
4/5 : ( 4/5 . -5/4) : ( 16/25 - 1/5 )
11/12 : ( 7/9 + -1/3 ) - ( 2/3 - 5/15 )
-2/5 . ( 9/8 + 16/32 -3/4 ) - 9/10
( 4/3 + 8/3 ) . ( 7/4 - 6/4 ) : ( 6/5 + 12/5 + 1/5 )
cách giải bài này như nào: 5/20+1/4+6/24+8/32=bao nhiêu
\(\dfrac{4}{5}\) : (\(\dfrac{4}{5}\) .- \(\dfrac{5}{4}\)) : (\(\dfrac{16}{25}\) - \(\dfrac{1}{5}\))
= \(\dfrac{4}{5}\) : (-1) : (\(\dfrac{16}{25}\) - \(\dfrac{5}{25}\))
= -\(\dfrac{4}{5}\) : \(\dfrac{11}{25}\)
= - \(\dfrac{4}{5}\) x \(\dfrac{25}{11}\)
= - \(\dfrac{20}{11}\)
\(\dfrac{11}{12}\) : (\(\dfrac{7}{9}\) + \(\dfrac{-1}{3}\)) - (\(\dfrac{2}{3}\) - \(\dfrac{5}{15}\))
= \(\dfrac{11}{12}\) : (\(\dfrac{7}{9}\) - \(\dfrac{3}{9}\)) - (\(\dfrac{2}{3}\) - \(\dfrac{1}{3}\))
= \(\dfrac{11}{12}\) : \(\dfrac{4}{9}\) - \(\dfrac{1}{3}\)
= \(\dfrac{11}{12}\) x \(\dfrac{9}{4}\) - \(\dfrac{1}{3}\)
= \(\dfrac{99}{48}\) - \(\dfrac{1}{3}\)
= \(\dfrac{99}{48}\) - \(\dfrac{16}{48}\)
= \(\dfrac{83}{48}\)
4/5 : ( 4/5 . -5/4) : ( 16/25 - 1/5 )
11/12 : ( 7/9 + -1/3 ) - ( 2/3 - 5/15 )
-2/5 . ( 9/8 + 16/32 -3/4 ) - 9/10
( 4/3 + 8/3 ) . ( 7/4 - 6/4 ) : ( 6/5 + 12/5 + 1/5 )
\(\dfrac{4}{5}\): (\(\dfrac{4}{5}\).-\(\dfrac{5}{4}\)) : (\(\dfrac{16}{25}\) - \(\dfrac{1}{5}\))
=\(\dfrac{4}{5}\) x - 1: (\(\dfrac{16}{25}\) - \(\dfrac{5}{25}\))
= - \(\dfrac{4}{5}\) : \(\dfrac{11}{25}\)
= - \(\dfrac{4}{5}\) x \(\dfrac{25}{11}\)
= - \(\dfrac{20}{11}\)
\(\dfrac{11}{12}\): (\(\dfrac{7}{9}\) + - \(\dfrac{1}{3}\)) - (\(\dfrac{2}{3}\) - \(\dfrac{5}{15}\))
= \(\dfrac{11}{12}\) : (\(\dfrac{7}{9}\) - \(\dfrac{3}{9}\)) - (\(\dfrac{2}{3}\) - \(\dfrac{1}{3}\))
= \(\dfrac{11}{12}\) : \(\dfrac{4}{9}\) - \(\dfrac{1}{3}\)
= \(\dfrac{11}{12}\) x \(\dfrac{9}{4}\) - \(\dfrac{1}{3}\)
= \(\dfrac{99}{48}\) - \(\dfrac{16}{48}\)
= \(\dfrac{83}{48}\)
- \(\dfrac{2}{5}\).(\(\dfrac{9}{8}\) + \(\dfrac{16}{32}\) - \(\dfrac{3}{4}\)) - \(\dfrac{9}{10}\)
= - \(\dfrac{2}{5}\).(\(\dfrac{9}{8}\) + \(\dfrac{4}{8}\) - \(\dfrac{6}{8}\)) - \(\dfrac{9}{10}\)
= - \(\dfrac{2}{5}\).(\(\dfrac{13}{8}\) - \(\dfrac{6}{8}\)) - \(\dfrac{9}{10}\)
= - \(\dfrac{2}{5}\).\(\dfrac{7}{8}\) - \(\dfrac{9}{10}\)
= - \(\dfrac{7}{20}\) - \(\dfrac{18}{20}\)
= - \(\dfrac{5}{4}\)
Tính
1. 6/5 - 1/4 + 4/5 - 3/4
2. 7/9 - 5/12 + 2/9 - 7/12
3. -4/15 + 5/13 - 11/15 + 8/13
4. 9/15 - 7/13 +6/15 - 6/13
5. 12/5 - 3/7 + 3/5 - 4/7
6. 6/5 - 1/4 + 4/5 - 3/4 + 1/2
7. 13/7 - 8/6 + 8/7 - 4/6 - 1/3
Tính:
a) -5/7(14/5 - 7/10) : |-2/3| - 3/4(8/9 + 16/3) + 10/3(1/3 + 1/5)
b) 17/-26(1/6 - 5/3) : 17/13 - 20/3(2/5 - 1/4) + 2/3(6/5 - 9/2)
c) -8/9(9/8 - 3/2) + 5/4 : (5/2 - 15/4) - 3/4(10/9 - 8/3) : (-1/3)
d) 21/10 : (12/5 - 9/10) . (-4/7) - 3/2(1/6 - 7/12) + 1/5(3/2 - 1/4)
a) Ta có: \(\dfrac{-5}{7}\left(\dfrac{14}{5}-\dfrac{7}{10}\right):\left|-\dfrac{2}{3}\right|-\dfrac{3}{4}\left(\dfrac{8}{9}+\dfrac{16}{3}\right)+\dfrac{10}{3}\left(\dfrac{1}{3}+\dfrac{1}{5}\right)\)
\(=\dfrac{-5}{7}\cdot\dfrac{3}{2}\cdot\dfrac{21}{10}-\dfrac{3}{4}\cdot\dfrac{56}{3}+\dfrac{10}{3}\cdot\dfrac{8}{15}\)
\(=\dfrac{-9}{4}-14+\dfrac{16}{9}\)
\(=\dfrac{-1621}{126}\)
b) Ta có: \(\dfrac{17}{-26}\cdot\left(\dfrac{1}{6}-\dfrac{5}{3}\right):\dfrac{17}{13}-\dfrac{20}{3}\left(\dfrac{2}{5}-\dfrac{1}{4}\right)+\dfrac{2}{3}\left(\dfrac{6}{5}-\dfrac{9}{2}\right)\)
\(=\dfrac{-17}{26}\cdot\dfrac{13}{17}\cdot\dfrac{-3}{2}-\dfrac{20}{3}\cdot\dfrac{3}{20}+\dfrac{2}{3}\cdot\dfrac{-33}{10}\)
\(=\dfrac{3}{4}-1-\dfrac{11}{5}\)
\(=-\dfrac{49}{20}\)
Sap xep cac phan so sau theo thu tu tu lon den be
8/9; 4/5; 9/8; 3/4; 10/9; 12/12; 7/8; 1/6; 1/4; 3/2; 1/5; 8/7; 6/5; 5/6; 4/3; 6/7; 2/3; 2/15; 1/2;5/4
Tính
1. 6/5 - 1/4 + 4/5 - 3/4
2. 7/9 - 5/12 + 2/9 - 7/12
3. -4/15 + 5/13 - 11/15 + 8/13
4. 9/15 - 7/13 +6/15 - 6/13
5. 12/5 - 3/7 + 3/5 - 4/7
6. 6/5 - 1/4 + 4/5 - 3/4 + 1/2
7. 13/7 - 8/6 + 8/7 - 4/6 - 1/3
6/5 có nghĩa là sáu phần năm đó nha mn
\(\frac{6}{5}-\frac{1}{4}+\frac{4}{5}-\frac{3}{4}\)
\(=\left(\frac{6}{5}+\frac{4}{5}\right)-\left(\frac{1}{4}+\frac{3}{4}\right)\)
\(=2-1\)
\(=1\)
\(\frac{7}{9}-\frac{5}{12}+\frac{2}{9}-\frac{7}{12}\)
\(=\left(\frac{7}{9}+\frac{2}{9}\right)-\left(\frac{5}{12}+\frac{7}{12}\right)\)
\(=1-1\)
\(=0\)
các câu sau tương tự
A=1
B=0
C=ÂM 8/15
D=0
E=2
F=3/2
H=2/3
LẦN SAU CHO KHÓ SÍU NHA LỚP 5 CŨNG LÀM ĐC
-1-2-3-4-5-.......-100
-2-4-6-8-....-100
-6-9-12-15-......-99
-1+2-3+4-5+6-......-99+100
4-8+12-16+...........+196-200
A = -1 - 2 - 3 - ... - 100
= -(1 + 2 + 3 + ... + 100)
= -100.101 : 2
= -5050
--------
B = -2 - 4 - 6 - ... - 100
= -(2 + 4 + 6 + ... + 100)
Số số hạng của B:
(100 - 2) : 2 + 1 = 50 (số)
B = -(100 + 2) . 50 : 2 = -2550
--------
C = -6 - 9 - 12 - ... - 99
= -(6 + 9 + 12 + ... + 99)
Số số hạng của C:
(99 - 6) : 3 + 1 = 32 (số)
C = -(99 + 6) . 32 : 2 = -1680
--------
D = 4 - 8 + 12 - 16 + ... + 196 - 200
Số số hạng của D:
(200 - 4) : 4 + 1 = 50 (số)
D = (4 - 8) + (12 - 16) + ... + (196 - 200)
= -4 + (-4) + ... + (-4) (25 số -4)
= -4.25
= -100
2/5+2/3+3/4
2/6+3/12
5/6+1/3
1/3+5/12+5/6
5/8+4/7
1/5+5/35
5/8+3/4
1/6+1/3+1/12
1/6+5/24+2/3
7/3+8/7
2/5+1/6
1/7+1/4+6/7+3/4
giúp với
và ai giải được gọi cụ
9/10
17/36
7/6
19/12
67/56
12/35
11/8
7/12
25/24
73/21
17/30
2
ok chưa bạn!
thực hiện phép tính :
a) 15/4:(1/8-7/16)-5/9.(3/5-(-12)/15)
b) 3/32-7/34-3,15+4/11+12/17
c) 1/5-3,5-3/2+1,25
d)12/17.(1-1/15)-12/17.(4/5-1)
e) 2,15:8/9-7/4:8/9+(-5/6)^2
f) 5/6 :-1/2+5/6:-1/4+2,3
g) (1/2-2/3)^2 : (-0,5)^2 : (-0,5)^2 + (1,25-3/2)^2 : 0,3
a: \(=\dfrac{15}{4}:\dfrac{2-7}{16}-\dfrac{5}{9}\cdot\left(\dfrac{3}{5}+\dfrac{4}{5}\right)\)
\(=\dfrac{15}{4}\cdot\dfrac{16}{-5}-\dfrac{5}{9}\cdot\dfrac{7}{5}\)
\(=\dfrac{-240}{20}-\dfrac{7}{9}=-12-\dfrac{7}{9}=\dfrac{-115}{9}\)
c: \(=\dfrac{1}{5}-\dfrac{7}{2}-\dfrac{3}{2}+\dfrac{5}{4}\)
\(=\dfrac{4+25}{20}-5=\dfrac{29}{20}-\dfrac{100}{20}=\dfrac{-71}{20}\)
d: \(=\dfrac{12}{17}\left(1-\dfrac{1}{15}-\dfrac{4}{5}+1\right)=\dfrac{12}{17}\cdot\dfrac{17}{15}=\dfrac{12}{15}=\dfrac{4}{5}\)
e: \(=\dfrac{2}{15}\cdot\dfrac{9}{8}-\dfrac{7}{4}\cdot\dfrac{9}{8}+\dfrac{25}{36}\)
\(=\dfrac{9}{8}\left(\dfrac{2}{15}-\dfrac{7}{4}\right)+\dfrac{25}{36}\)
\(=\dfrac{9}{8}\cdot\dfrac{8-105}{60}+\dfrac{25}{36}\)
\(=\dfrac{9}{8}\cdot\dfrac{-97}{60}+\dfrac{25}{36}=\dfrac{-1619}{1440}\)