Tính giá trị biểu thức :
a) \(5\dfrac{5}{27}+\dfrac{7}{23}+0,5-\dfrac{5}{27}+\dfrac{16}{23}\)
b) \(\dfrac{3}{8}.27\dfrac{1}{5}-51.\dfrac{1}{5}.\dfrac{3}{8}+19\)
Những câu hỏi liên quan
I. thực hiện phép tính
a. 5-2timesleft(dfrac{-1}{2}right)^2
b. left(4-dfrac{1}{2}right)^3+dfrac{1}{2}
c. 5dfrac{5}{27}+dfrac{7}{23}+0,5-dfrac{5}{27}+dfrac{16}{23}
d. 19+dfrac{3}{8}times27dfrac{1}{5}times51dfrac{1}{5}timesdfrac{3}{8}
e. 35dfrac{1}{6}divdfrac{-4}{5}-45dfrac{1}{6}divdfrac{-4}{5}
Đọc tiếp
I. thực hiện phép tính
a. \(5-2\times\left(\dfrac{-1}{2}\right)^2\)
b. \(\left(4-\dfrac{1}{2}\right)^3+\dfrac{1}{2}\)
c. \(5\dfrac{5}{27}+\dfrac{7}{23}+0,5-\dfrac{5}{27}+\dfrac{16}{23}\)
d. \(19+\dfrac{3}{8}\times27\dfrac{1}{5}\times51\dfrac{1}{5}\times\dfrac{3}{8}\)
e. \(35\dfrac{1}{6}\div\dfrac{-4}{5}-45\dfrac{1}{6}\div\dfrac{-4}{5}\)
a: \(=5-2\cdot\dfrac{1}{4}=5-\dfrac{1}{2}=\dfrac{9}{2}\)
b: \(=\left(\dfrac{7}{2}\right)^3+\dfrac{1}{2}=\dfrac{343}{8}+\dfrac{1}{2}=\dfrac{347}{8}\)
c: \(=\left(5+\dfrac{5}{27}-\dfrac{5}{27}\right)+\left(\dfrac{7}{23}+\dfrac{16}{23}\right)-\dfrac{1}{2}=5+1-\dfrac{1}{2}=5+\dfrac{1}{2}=5.5\)
e: \(=\dfrac{-5}{4}\left(35+\dfrac{1}{6}-45-\dfrac{1}{6}\right)=\dfrac{-5}{4}\cdot\left(-10\right)=\dfrac{50}{4}=\dfrac{25}{2}\)
Đúng 0
Bình luận (0)
\(a,\dfrac{3}{5}+\dfrac{-5}{9}\)
\(b,\dfrac{1}{3}+\dfrac{-4}{3};\dfrac{4}{7}\)
\(c,-\dfrac{27}{23}+\dfrac{5}{21}+\dfrac{4}{23}+\dfrac{16}{21}+\dfrac{1}{2}\)
\(d,\dfrac{-8}{9}+\dfrac{1}{9}.\dfrac{2}{9}+\dfrac{1}{9}.\dfrac{7}{9}\)
\(a,\dfrac{3}{5}+\dfrac{-5}{9}=\dfrac{27-25}{45}=\dfrac{2}{49}.\)
\(c,\dfrac{-27}{23}+\dfrac{5}{21}+\dfrac{4}{23}+\dfrac{16}{21}+\dfrac{1}{2}=\dfrac{-23}{23}+\dfrac{21}{21}+\dfrac{1}{2}=-1+1+\dfrac{1}{2}=\dfrac{1}{2}.\)
\(d,\dfrac{-8}{9}+\dfrac{1}{9}.\dfrac{2}{9}+\dfrac{1}{9}.\dfrac{7}{9}=\dfrac{-8}{9}+\dfrac{1}{9}.\left(\dfrac{2}{9}+\dfrac{7}{9}\right)=\dfrac{-8}{9}+\dfrac{1}{9}.1=\dfrac{-8+1}{9}=\dfrac{-7}{9}.\)
Đúng 1
Bình luận (0)
5dfrac{5}{27}+dfrac{7}{23}-0,5.dfrac{5}{27}+dfrac{16}{23}
45dfrac{1}{6}:left(dfrac{-4}{5}right)-35dfrac{1}{6}:left(dfrac{-4}{5}right)
25.left(dfrac{-1}{5}right)^3+dfrac{1}{5}-2.left(dfrac{-1}{2}right)^2-dfrac{1}{2}
left(3,1-2,5right)-left(-2,5-3,1right)
dfrac{3}{8}.dfrac{7}{5}-dfrac{7}{5}.dfrac{1}{8}+dfrac{13}{20}
CẦN GẤP NGAY VÀ LUÔN :)))))
Đọc tiếp
\(5\dfrac{5}{27}+\dfrac{7}{23}-0,5.\dfrac{5}{27}+\dfrac{16}{23}=\)
\(45\dfrac{1}{6}:\left(\dfrac{-4}{5}\right)-35\dfrac{1}{6}:\left(\dfrac{-4}{5}\right)=\)
\(25.\left(\dfrac{-1}{5}\right)^3+\dfrac{1}{5}-2.\left(\dfrac{-1}{2}\right)^2-\dfrac{1}{2}=\)
\(\left(3,1-2,5\right)-\left(-2,5-3,1\right)=\)
\(\dfrac{3}{8}.\dfrac{7}{5}-\dfrac{7}{5}.\dfrac{1}{8}+\dfrac{13}{20}=\)
CẦN GẤP NGAY VÀ LUÔN :)))))
SGK Kết nối tri thức với cuộc sống - Trang 74
24 tháng 8 2023 lúc 0:25
Tính (theo mẫu).
Mẫu: \(\dfrac{2}{3}+\dfrac{5}{3}=\dfrac{2+5}{3}=\dfrac{7}{3}\)
a) \(\dfrac{2}{7}+\dfrac{4}{7}\) b) \(\dfrac{23}{13}+\dfrac{8}{13}\) c) \(\dfrac{27}{125}+\dfrac{16}{125}\)
a) \(\dfrac{2}{7}+\dfrac{4}{7}=\dfrac{2+4}{7}=\dfrac{6}{7}\)
b) \(\dfrac{23}{13}+\dfrac{8}{13}=\dfrac{23+8}{13}=\dfrac{31}{13}\)
c) \(\dfrac{27}{125}+\dfrac{16}{125}=\dfrac{27+16}{125}=\dfrac{43}{125}\)
Đúng 2
Bình luận (0)
a)\(\dfrac{2}{7}\) + \(\dfrac{4}{7}\) = \(\dfrac{6}{7}\)
b)\(\dfrac{23}{13}\) + \(\dfrac{8}{13}\) = \(\dfrac{31}{13}\)
c)\(\dfrac{27}{125}\) + \(\dfrac{16}{125}\) = \(\dfrac{43}{125}\)
Đúng 0
Bình luận (0)
4 tháng 10 2021 lúc 8:21
Tính nhanh (nếu có thể):
a) \(5\dfrac{5}{27}+\dfrac{7}{23}+0,5.\dfrac{5}{27}+\dfrac{16}{23}\)
b) \(\dfrac{10^9.49^4}{14^8.25^5}\)
các bn ghi rõ cách giải giùm mình đcc ko, mình cảm ơn 
a) https://hoc247.net/hoi-dap/toan-7/thuc-hien-phep-tinh-5-5-27-7-23-0-5-5-27-16-23-faq218258.html
b) https://hoidap247.com/cau-hoi/1507941
Đúng 1
Bình luận (1)
b) \(\dfrac{10^9.49^4}{14^8.25^5}=\dfrac{\left(2.5\right)^9.\left(7^2\right)^4}{\left(7.2\right)^8.\left(5^2\right)^5}=\dfrac{2^9.5^9.7^6}{7^8.2^8.5^{10}}=\dfrac{2}{7.7.5}=\dfrac{2}{245}\)
Đúng 1
Bình luận (3)
\(a,=\left(\dfrac{140}{27}+\dfrac{1}{2}\cdot\dfrac{5}{27}\right)+\left(\dfrac{7}{23}+\dfrac{16}{23}\right)\\ =\left(\dfrac{140}{27}+\dfrac{5}{54}\right)+1=\dfrac{285}{54}+1=\dfrac{339}{54}=\dfrac{113}{18}\\ b,=\dfrac{2^9\cdot5^9\cdot7^8}{7^8\cdot2^8\cdot5^{10}}=\dfrac{2}{5}\)
Đúng 2
Bình luận (1)
bài 3 thực hiện phép tínhadfrac{5}{8}+dfrac{3}{17}+dfrac{4}{18}+dfrac{20}{-17}+dfrac{-2}{9}+dfrac{21}{56}bleft(dfrac{9}{16}+dfrac{8}{-27}right)+left(1+dfrac{7}{16}+dfrac{-19}{27}right)cleft(dfrac{13}{5}+dfrac{7}{16}right)+left(dfrac{-15}{16}+dfrac{6}{15}right) d left(6-2dfrac{4}{5}right).3dfrac{1}{8}-1dfrac{3}{5}:dfrac{1}{4}
Đọc tiếp
bài 3 thực hiện phép tính
a\(\dfrac{5}{8}+\dfrac{3}{17}+\dfrac{4}{18}+\dfrac{20}{-17}+\dfrac{-2}{9}+\dfrac{21}{56}\)
b\(\left(\dfrac{9}{16}+\dfrac{8}{-27}\right)+\left(1+\dfrac{7}{16}+\dfrac{-19}{27}\right)\)
c\(\left(\dfrac{13}{5}+\dfrac{7}{16}\right)+\left(\dfrac{-15}{16}+\dfrac{6}{15}\right)\) d \(\left(6-2\dfrac{4}{5}\right).3\dfrac{1}{8}-1\dfrac{3}{5}:\dfrac{1}{4}\)
a) Ta có: \(\dfrac{5}{8}+\dfrac{3}{17}+\dfrac{4}{18}+\dfrac{20}{-17}+\dfrac{-2}{9}+\dfrac{21}{56}\)
\(=\left(\dfrac{3}{17}-\dfrac{20}{17}\right)+\left(\dfrac{2}{9}-\dfrac{2}{9}\right)+\left(\dfrac{5}{8}+\dfrac{3}{8}\right)\)
\(=-1+1=0\)
b) Ta có: \(\left(\dfrac{9}{16}+\dfrac{8}{-27}\right)+\left(1+\dfrac{7}{16}+\dfrac{-19}{27}\right)\)
\(=\left(\dfrac{9}{16}+\dfrac{7}{16}\right)+\left(\dfrac{-8}{27}-\dfrac{19}{27}\right)+1\)
=1-1+1=1
Đúng 2
Bình luận (1)
(1,5 điểm) Tính giá trị của biểu thức.
a) $\dfrac{7}{2}-\left(\dfrac{3}{4}+\dfrac{1}{5}\right)$
b) $\dfrac{12}{23} . \dfrac{7}{13}+\dfrac{11}{23} . \dfrac{7}{13};$
c) $|-2|-\left(\dfrac{5}{9}-\dfrac{2}{3}\right)^2: \dfrac{4}{27}.$
a) 7/2 - (3/4 + 1/5)
= 7/2 - 19/20
= 51/20
b) 12/23 . 7/13 + 11/23 . 7/13
= 7/13 . (12/23 + 11/23)
= 7/13 . 1
= 7/13
c) |-2| - (5/9 - 2/3)² : 4/27
= 2 - 1/81 : 4/27
= 2 - 1/12
= 23/12
Đúng 2
Bình luận (0)
a) 7/2 - (3/4 + 1/5)
= 7/2 - 19/20
= 51/20
b) 12/23 . 7/13 + 11/23 . 7/13
= 7/13 . (12/23 + 11/23)
= 7/13 . 1
= 7/13
c) |-2| - (5/9 - 2/3)² : 4/27
= 2 - 1/81 : 4/27
= 2 - 1/12
= 23/12
Đúng 0
Bình luận (0)
a) \(\dfrac{7}{2}\)-(\(\dfrac{3}{4}\)+\(\dfrac{1}{5}\))
=\(\dfrac{7}{2}\)-(\(\dfrac{15}{20}\)+\(\dfrac{4}{20}\))
=\(\dfrac{7}{2}\)-\(\dfrac{19}{20}\)
=\(\dfrac{70}{20}\)-\(\dfrac{19}{20}\)
\(\dfrac{51}{20}\)
b) \(\dfrac{12}{23}\).\(\dfrac{7}{13}\)+\(\dfrac{11}{23}\).\(\dfrac{7}{13}\)
=\(\dfrac{7}{13}\).(\(\dfrac{12}{23}\)+\(\dfrac{11}{23}\))
=\(\dfrac{7}{13}\).1
=\(\dfrac{7}{13}\)
c) ∣−2∣-(\(\dfrac{5}{9}\)-\(\dfrac{2}{3}\))\(^2\):\(\dfrac{4}{27}\)
= 2-(\(\dfrac{-1}{9}\))\(^2\):\(\dfrac{4}{27}\)
= 2-\(\dfrac{1}{81}\):\(\dfrac{4}{27}\)
= 2-\(\dfrac{1}{12}\)
\(\dfrac{23}{12}\)
Đúng 0
Bình luận (0)
dfrac{4}{9}.19dfrac{1}{3}+dfrac{-4}{9}.39dfrac{1}{3}+dfrac{-3^2}{5}:left(-0,2right)
dfrac{left(-5^3right)^2}{27}.dfrac{3}{23}.dfrac{6^2}{-5^6}
1dfrac{4}{23}+dfrac{5}{21}-dfrac{4}{23}+0,5+dfrac{16}{21}
dfrac{3}{7}.19dfrac{1}{3}-dfrac{3}{7}:33dfrac{1}{3}
dfrac{3}{4}-left(x+dfrac{1}{2}right)dfrac{4}{5}
x:(-2,14)(-3,12):1,2
Đọc tiếp
\(\dfrac{4}{9}.19\dfrac{1}{3}+\dfrac{-4}{9}.39\dfrac{1}{3}+\dfrac{-3^2}{5}:\left(-0,2\right)\)
\(\dfrac{\left(-5^3\right)^2}{27}.\dfrac{3}{23}.\dfrac{6^2}{-5^6}\)
\(1\dfrac{4}{23}+\dfrac{5}{21}-\dfrac{4}{23}+0,5+\dfrac{16}{21}\)
\(\dfrac{3}{7}.19\dfrac{1}{3}-\dfrac{3}{7}:33\dfrac{1}{3}\)
\(\dfrac{3}{4}-\left(x+\dfrac{1}{2}\right)=\dfrac{4}{5}\)
x:(-2,14)=(-3,12):1,2
Tính 1 câu thoy nhé !
\(\dfrac{3}{7}.19\dfrac{1}{3}-\dfrac{3}{7}.33\dfrac{1}{3}\)
= \(\dfrac{3}{7}.\left(19\dfrac{1}{3}-33\dfrac{1}{3}\right)\)
=\(\dfrac{3}{7}.-14=-6\)
Đúng 0
Bình luận (0)
Tính:
a) \(\dfrac{17}{8}:\left(\dfrac{27}{8}+\dfrac{11}{2}\right);\)
b) \(\dfrac{28}{15}\cdot\dfrac{1}{4^2}.3+\left(\dfrac{8}{15}-\dfrac{69}{60}\cdot\dfrac{5}{23}\right):\dfrac{51}{54}.\)
\(a.\)
\(\dfrac{17}{8}:\left(\dfrac{27}{8}+\dfrac{11}{2}\right)\)
\(=\dfrac{17}{8}:\left(\dfrac{27+44}{8}\right)=\dfrac{17}{8}:\dfrac{71}{8}=\dfrac{17}{8}\cdot\dfrac{8}{71}=\dfrac{17}{71}\)
\(b.\)
\(\dfrac{28}{15}\cdot\dfrac{1}{4^2}\cdot3+\left(\dfrac{8}{15}-\dfrac{69}{60}\cdot\dfrac{5}{23}\right):\dfrac{51}{54}\)
\(=\dfrac{28}{15}\cdot\dfrac{1}{4^2}\cdot3+\left(\dfrac{8}{15}-\dfrac{1}{4}\right):\dfrac{51}{54}\)
\(=\dfrac{28}{15}\cdot\dfrac{1}{4^2}\cdot3+\left(\dfrac{8\cdot4-15}{60}\right):\dfrac{51}{54}\)
\(=\dfrac{28}{15}\cdot\dfrac{1}{4^2}\cdot3+\dfrac{17}{60}:\dfrac{51}{54}\)
\(=\dfrac{28}{15}\cdot\dfrac{1}{16}\cdot3+\dfrac{17}{60}\cdot\dfrac{54}{51}\)
\(=\dfrac{7}{20}+\dfrac{3}{10}\)
\(=\dfrac{7+3\cdot2}{20}=\dfrac{13}{20}\)
Đúng 1
Bình luận (0)
