tính
a)(1,11+0,19-2,6):(2,06+0,54)-(\(\frac{1}{2}+\frac{1}{3}\)):2
b)(\(2\frac{1}{3}+3,5\)):(\(-4\frac{1}{6}+3\frac{1}{7}\))+7,5
Tính bằng cách hợp lí:
\(\left(1,11+0,19-2,6\right):\left(2,06+0,54\right)-\left(\frac{1}{2}+\frac{1}{3}\right):2\)
Giúp mị với , mị cảm ơn
Tính :
a)\(\frac{0,8\times0,44\times1,25\times25}{10\times125\times4\times25\times8}\) b)\(\frac{13,5\times1420+4,5\times580\times3}{3+6+9+.....+24+27}\)
c)\((1,11+0,19-2.6):(2,06+0,54)-(\frac{1}{2}+\frac{1}{3}):2\)
d)\([2\frac{1}{3}+3,5]:[-4\frac{1}{6}+3\times\frac{1}{7}]+7,5\)
e)\(-15,5\times20,8+3,5\times9,2-15,5\times9,2+3.5\times20,8\)
Giúp mk với , thanks nhiều ạ
Bài1.Tính hợp lí:
a) (1,11+0,19-2,6):(2,06+0,54)-(\(\dfrac{1}{2}+\dfrac{1}{3}\)):2
b) (2\(\dfrac{1}{3}\)+3,5):(-4\(\dfrac{1}{6}+3\dfrac{1}{7}\))+7,5
a: \(=\left(1.3-2.6\right):\left(2.6\right)-\dfrac{5}{6}:2\)
\(=\dfrac{-1.3}{2.6}-\dfrac{5}{12}\)
\(=\dfrac{-1}{2}-\dfrac{5}{12}=\dfrac{-11}{12}\)
b: \(=\left(\dfrac{7}{3}+\dfrac{7}{2}\right):\left(-\dfrac{25}{6}+\dfrac{22}{7}\right)+\dfrac{15}{2}\)
\(=\dfrac{35}{6}:\dfrac{-175+132}{42}+\dfrac{15}{2}\)
\(=\dfrac{-35}{6}\cdot\dfrac{42}{43}+\dfrac{15}{2}=\dfrac{155}{86}\)
+) A = ( 1,11 + 0,19 - 2,6 ) : ( 2,06 + 0,54 ) - ( \(\frac{1}{2}\) + \(\frac{1}{3}\) ) : 2
+) Tìm x :
a, (1,16 - x ) . 2,25 / 10 \(\frac{5}{9}\) - 7\(\frac{1}{4}\) . 2\(\frac{2}{11}\) = 75%
b) x + 25% .x = -1,25
c) x - 75% x = \(\frac{1}{4}\)
+) Tính nhanh nếu có thể :
a) 1\(\frac{1}{2}\) - 3\(\frac{3}{4}\) b) -8\(\frac{1}{6}\) - 7\(\frac{3}{2}\) c) 0,15 - 4,8 + 1,3 d) ( 2\(\frac{1}{3}\) + 3,5 ) : (-4\(\frac{1}{6}\) + 3\(\frac{1}{7}\) ) + 7,5
e) 11\(\frac{1}{4}\) + (2\(\frac{5}{7}\) + 5\(\frac{1}{4}\) ) f) \(\frac{4}{9}\) : ( \(\frac{1}{-7}\) + 6\(\frac{5}{9}\) :(-\(\frac{1}{7}\))
Bài 2:
b: x+25%x=-1,25
=>1,25x=-1,25
hay x=-1
c: x-75%x=1/4
=>1/4x=1/4
hay x=1
Bài 2:
a: =3/2-11/4=6/4-11/4=-5/4
b: =-49/6-17/2=-49/6-51/6=-100/6=-50/3
Bài 1) Cho \(A=\frac{1,11+0,19-1,3.2}{2,06+0,54}-\left(\frac{1}{2}+\frac{1}{3}\right):2\) và \(B=\left(5\frac{7}{8}-2\frac{1}{4}-0,5\right):2\frac{23}{26}\). Tìm x\(\in\)Z để A<x<B
\(A=\frac{1,11+0,19-1,3.2}{2,06+0,54}-\left(\frac{1}{2}+\frac{1}{3}\right):2=\frac{-\frac{131}{100}}{\frac{13}{5}}-\frac{5}{6}:2\)
\(=-\frac{131}{260}-\frac{5}{12}=-\frac{359}{390}\)
\(B=\left(5\frac{7}{8}-2\frac{1}{4}-0,5\right):2\frac{23}{26}=\left(\frac{47}{8}-\frac{9}{4}-\frac{1}{2}\right):\frac{75}{26}=\frac{25}{8}.\frac{26}{75}=\frac{13}{12}\)
Ta có : \(A=-\frac{359}{390}\approx-0,9\)
\(B=\frac{13}{12}\approx1,08\)
\(\Rightarrow A< x< B\) mà x nguyên \(\Rightarrow\left[{}\begin{matrix}x=0\\x=1\end{matrix}\right.\)
Ta có:
\(A=\frac{1,11+0,19-1,3.2}{2,06+0,54}-\left(\frac{1}{2}+\frac{1}{3}\right):2=\frac{\frac{-13}{10}}{\frac{13}{5}}-\frac{5}{6}:2=\frac{-1}{2}-\frac{5}{12}=\frac{-11}{12}\)
\(B=\left(5\frac{7}{8}-2\frac{1}{4}-0,5\right):2\frac{23}{26}=\left(\frac{47}{8}-\frac{9}{4}-\frac{1}{2}\right):\frac{75}{26}=\frac{25}{8}:\frac{75}{26}=\frac{13}{12}\)
\(\Rightarrow A< x< B\Rightarrow\frac{-11}{12}< x< \frac{13}{12}\Rightarrow-1< x\le1\Rightarrow x\in\left\{0;1\right\}\)
Cho \(A=\frac{1,11+0,19-1,3.2}{2,06+0,54}-\left(\frac{1}{2}+\frac{1}{3}\right):2\)
\(B=\left(5\frac{7}{8}-2\frac{1}{4}-0,5\right):2\frac{23}{26}\)
a) Rút gọn A và B
b) Tìm x thuộc Z để A<x<B
A= \(\frac{1,11+0,19-1,3.2}{2,06+0,54}-\left(\frac{1}{2}+\frac{1}{3}\right):2=\frac{-\frac{131}{100}}{\frac{13}{5}}-\frac{5}{6}:2\)
=\(-\frac{131}{260}-\frac{5}{12}=-\frac{359}{390}\)
B= \(\left(5\frac{7}{8}-2\frac{1}{4}-0,5\right):2\frac{23}{26}=\left(\frac{47}{8}-\frac{9}{4}-\frac{1}{2}\right):\frac{75}{26}=\frac{25}{8}.\frac{26}{75}=\frac{13}{12}\)
b) ta có : A=\(-\frac{359}{390}\approx-0,9\)
B= \(\frac{13}{12}\approx1,08\)
=> A<x<B mà x nguyên => x=0 hoặc x=1
1) \(\left(\frac{1,5+1-0,5}{2,5+\frac{5}{3}-1,25}+\frac{0,375-0,3+\frac{3}{11}+\frac{3}{12}}{-0,625+0,5-\frac{5}{11}-\frac{5}{12}}\right):\frac{1890}{2005}+115\)
2) A=\(\frac{1,11+0,19-1,3.2}{2,06+0,54}-\left(\frac{1}{3}+\frac{1}{2}\right):2\)
3) A= \(1+\frac{3}{2^3}+\frac{4}{2^4}+...+\frac{100}{2^{100}}\)
giúp mik nha
a>\(\frac{1,11+0,19-1,3.2}{2,06+0,54}-\left(\frac{1}{2}+\frac{1}{3}\right):2\)
b> (-15,5).20,8+3,5.9,2-15,5.9,2+3,5.20,8
\(A=\frac{1,11+0,19-1,3\times2}{2,06+0,54}-(\frac{1}{2}+\frac{1}{3}):2\)
\(B=(5\frac{7}{8}-2\frac{1}{4}-0,5):2\frac{23}{26}\)
a. Rút gọn A và B
b. Tìm x\(\in\)Z để A<x<B