\(\dfrac{x}{36}\)= \(\dfrac{-2}{3}\)+ \(\dfrac{5}{12}\)
b) \(\dfrac{2}{5}\)+\(\dfrac{3}{5}\):(\(\dfrac{3}{5}\)+\(\dfrac{-2}{3}\))\(-3\dfrac{1}{2}\)
c) (\(4-\dfrac{5}{12}\)):3+\(\dfrac{7}{36}\)
d) (\(2+\dfrac{5}{6}\)):\(1\dfrac{1}{5}\)+\(\dfrac{-7}{12}\)
b: \(=\dfrac{2}{5}+\dfrac{3}{5}:\dfrac{9-10}{15}-\dfrac{7}{2}\)
\(=\dfrac{4-35}{10}+\dfrac{3}{5}\cdot\dfrac{15}{-1}\)
\(=\dfrac{-31}{10}-9=\dfrac{-31}{10}-\dfrac{90}{10}=-\dfrac{121}{10}\)
c: \(=\dfrac{48-5}{12}\cdot\dfrac{1}{3}+\dfrac{7}{36}=\dfrac{43}{36}+\dfrac{7}{36}=\dfrac{50}{36}=\dfrac{25}{18}\)
d: \(=\dfrac{17}{6}:\dfrac{6}{5}+\dfrac{-7}{12}\)
\(=\dfrac{85}{36}-\dfrac{7}{12}=\dfrac{85}{36}-\dfrac{21}{36}=\dfrac{64}{36}=\dfrac{16}{9}\)
\(\dfrac{7}{12}+\dfrac{5}{36}:x=\dfrac{3}{4}\)
=>5/36:x=3/4-7/12=9/12-7/12=1/6
=>x=5/36:1/6=5/36x6=5/6
7/12 + 5/36 : x = 3/4
5/36 : x = 7/12 + 3/4
5/36 : x = 4/3
x = 5/36 : 4/3
x = 5/48
vậy x =...
21/36 + 5/36 : x = 3/4
13/18 : x = 3/4
x = 3/4 x 18/13
x = 27/26
Tính hợp lý:
\(A=\dfrac{7}{12}+\dfrac{5}{12}:6-\dfrac{11}{36}\) \(B=\left(\dfrac{4}{5}+\dfrac{1}{2}\right):\left(\dfrac{3}{13}-\dfrac{8}{13}\right)\)
\(C=\left(\dfrac{2}{3}-\dfrac{1}{4}+\dfrac{5}{11}\right):\left(\dfrac{5}{12}+1-\dfrac{7}{11}\right)\)
a: \(A=\dfrac{7}{12}+\dfrac{5}{72}-\dfrac{11}{36}=\dfrac{42}{72}+\dfrac{5}{72}-\dfrac{22}{72}=\dfrac{25}{72}\)
b: \(B=\dfrac{8+5}{10}:\dfrac{-5}{13}=\dfrac{13}{10}\cdot\dfrac{13}{-5}=-\dfrac{169}{100}\)
c: \(C=\left(\dfrac{88}{132}-\dfrac{33}{132}+\dfrac{60}{132}\right):\left(\dfrac{55}{132}+\dfrac{132}{132}-\dfrac{84}{132}\right)\)
\(=\dfrac{88-33+60}{55+132-84}=\dfrac{115}{103}\)
Trong một dãy tính chỉ có phép cộng và phép trừ phân số, ta thực hiện phép tính theo thứ tự từ trái sang phải :
Tính :
\(\dfrac{2}{9}+\dfrac{5}{-12}-\dfrac{-3}{4}\)
Điền số thích hợp vào chỗ trống để hoàn thành phép tính :
\(\dfrac{2}{9}+\dfrac{5}{-12}-\dfrac{-3}{4}=\dfrac{2}{9}+\dfrac{-5}{12}+\dfrac{3}{4}=\dfrac{2.4}{36}+\dfrac{\left(-5\right).....}{36}+\dfrac{3......}{36}=\dfrac{8-....+.....}{36}=\dfrac{20}{36}=\dfrac{....}{....}\)
Viết tập hợp A các số tự nhiên x sao cho:
a, \(\dfrac{-36}{9}\) ≤ x < \(\dfrac{-15}{5}\)
b, \(\dfrac{-27}{3}\) < x ≤ \(\dfrac{12}{4}\)
c, \(\dfrac{-21}{7}\) < x < \(\dfrac{-12}{6}\)
a: \(\Leftrightarrow-4< =x< =-3\)
hay \(x\in\varnothing\)
b: =>-9<x<=3
hay \(x\in\left\{0;1;2;3\right\}\)
\(a,\dfrac{-6}{11}:\left(\dfrac{3}{5}:\dfrac{4}{11}\right)\) b,\(\dfrac{7}{12}+\dfrac{5}{12}:6-\dfrac{11}{36}\)
\(c,\left(\dfrac{4}{5}+\dfrac{1}{2}\right):\left(\dfrac{3}{13}-\dfrac{8}{13}\right)\) \(d,\left(\dfrac{2}{3}-\dfrac{1}{4}+\dfrac{5}{11}\right):\left(\dfrac{5}{12}-1-\dfrac{7}{11}\right)\)
Giúp mik nha:>>
a: \(=\dfrac{-6}{11}:\dfrac{3\cdot11}{4\cdot5}=\dfrac{-6}{11}\cdot\dfrac{20}{33}=\dfrac{-2}{11}\cdot\dfrac{20}{11}=\dfrac{-40}{121}\)
b: \(=\dfrac{7}{12}+\dfrac{5}{72}-\dfrac{11}{36}=\dfrac{42}{72}+\dfrac{5}{72}-\dfrac{22}{72}=\dfrac{25}{72}\)
c: \(=\dfrac{13}{10}:\dfrac{-5}{13}=\dfrac{-169}{50}\)
Quy đồng mẫu số các phân số:
a) \(\dfrac{3}{4}\) và \(\dfrac{2}{5}\); b) \(\dfrac{5}{12}\) và \(\dfrac{11}{36}\); c) \(\dfrac{2}{3}\); \(\dfrac{3}{4}\) và \(\dfrac{4}{5}\).
a) \(\dfrac{3}{4}=\dfrac{3\cdot5}{4\cdot5}=\dfrac{15}{20}\\ \dfrac{2}{5}=\dfrac{2\cdot4}{5\cdot4}=\dfrac{8}{20}\)
b) \(\dfrac{5}{12}=\dfrac{5\cdot3}{12\cdot3}=\dfrac{15}{36}\\ \dfrac{11}{36}=\dfrac{11}{36}\)
c) \(\dfrac{2}{3}=\dfrac{2\cdot4\cdot5}{3\cdot4\cdot5}=\dfrac{40}{60}\\ \dfrac{3}{4}=\dfrac{3\cdot3\cdot5}{4\cdot3\cdot5}=\dfrac{45}{60}\\ \dfrac{4}{5}=\dfrac{4\cdot3\cdot4}{5\cdot3\cdot4}=\dfrac{48}{60}\)
a) \(\dfrac{3}{4}\) và \(\dfrac{2}{5}\)
Mẫu số chung: 20
\(\dfrac{3}{4}=\dfrac{3.5}{4.5}=\dfrac{15}{20}\)
\(\dfrac{2}{5}=\dfrac{2.4}{5.4}=\dfrac{8}{20}\)
b) \(\dfrac{5}{12}\) và \(\dfrac{11}{36}\)
Mẫu số chung: 36
\(\dfrac{5}{12}=\dfrac{5.3}{12.3}=\dfrac{15}{36}\)
c) \(\dfrac{2}{3};\dfrac{3}{4}\) và \(\dfrac{4}{5}\)
Mẫu số chung: 60
\(\dfrac{2}{3}=\dfrac{2.20}{3.20}=\dfrac{40}{60}\\ \dfrac{3}{4}=\dfrac{3.15}{4.15}=\dfrac{45}{60}\\ \dfrac{4}{5}=\dfrac{4.12}{5.12}=\dfrac{48}{60}\)
a) MTC=20
\(\dfrac{3}{4}=\dfrac{15}{20}\)
\(\dfrac{2}{5}=\dfrac{8}{20}\)
b) MTC=36
\(\dfrac{5}{12}=\dfrac{15}{36}\)
\(\dfrac{11}{36}=\dfrac{11}{36}\)
c) MTC=60
\(\dfrac{2}{3}=\dfrac{40}{60}\)
\(\dfrac{3}{4}=\dfrac{45}{60}\)
\(\dfrac{4}{5}=\dfrac{48}{60}\)
bài 2:
\(\dfrac{11}{12}\)-\(\dfrac{5}{12}\)=...... \(\dfrac{25}{24}\)-\(\dfrac{16}{24}\)=...... \(\dfrac{27}{36}\)-\(\dfrac{15}{36}\)=.......
11/12-5/12=6/12=1/2
25/24-16/24=9/24=3/8
27/36-15/36=12/36=2/3
k cho mik nhé
A= ( -6,17 + \(3\dfrac{5}{9}\) - \(2\dfrac{36}{97}\)) . (\(\dfrac{1}{3}\) - 0,25 - \(\dfrac{1}{12}\))
B= \(\dfrac{0,5-\dfrac{3}{17}}{\dfrac{5}{6}-\dfrac{5}{17}}\) + \(\dfrac{0,5-\dfrac{1}{3}-0,2}{\dfrac{7}{5}+\dfrac{7}{3}-3,5}\)
A = \(\left(-6,17+3\dfrac{5}{9}-2\dfrac{36}{97}\right)\) . \(\left(\dfrac{1}{3}-0,25-\dfrac{1}{12}\right)\)
A = \(\left(-6,17+\dfrac{32}{9}-\dfrac{230}{97}\right)\) . \(\left(\dfrac{1}{3}-\dfrac{1}{4}-\dfrac{1}{12}\right)\)
A = \(\left(-6,17+\dfrac{32}{9}-\dfrac{230}{97}\right)\) . \(\left(\dfrac{4}{12}-\dfrac{3}{12}-\dfrac{1}{12}\right)\)
A = \(\left(-6,17+\dfrac{32}{9}-\dfrac{230}{97}\right)\) . 0
A = 0*
*Vì số nào nhân với 0 cũng bằng 0 nên không cần tính kết quả của phép tính\(\left(-6,17+\dfrac{32}{9}-\dfrac{230}{97}\right)\)
Tính (Tính hợp lí nếu có thể)
a) \(\dfrac{-7}{12}\)-\(\dfrac{3}{36}\)
b) (4-\(\dfrac{5}{12}\)):2+\(\dfrac{5}{24}\)
c) \(\dfrac{8}{9}\)+\(\dfrac{1}{9}\).\(\dfrac{2}{13}\)+\(\dfrac{1}{9}\).\(\dfrac{11}{13}\)
d) \(\dfrac{3}{4}\).\(\dfrac{8}{9}\).\(\dfrac{15}{16}\). ... .\(\dfrac{9999}{10000}\)
e) \(\dfrac{3}{1.4}\)+\(\dfrac{3}{4.7}\)+\(\dfrac{3}{7.10}\)+...+\(\dfrac{3}{97.100}\)
*Lưu ý: Mong các anh chị trình bày chi tiết để em có thể hiểu bài, em xin các anh chị đừng viết mỗi kết quả xong em chả biết một cái gì ;-;
a: =-21/36-3/36=-24/36=-2/3
b: =43/12*1/2+5/24=43/24+5/24=2
c: =8/9+1/9=1
e: =1-1/4+1/4-1/7+...+1/97-1/100
=1-1/100=99/100