câu 1 . Thực hiện phép tính a. 0,05 5 - \(\dfrac{1}{2}\) b. \(\dfrac{6}{15}-\dfrac{7}{8} 3-\dfrac{3}{5}-\dfrac{2}{16}\) c. \(\dfrac{3}{5}.\dfrac{15}{7}-\dfrac{15}{7}.\dfrac{8}{5}\) d. \(\dfrac{2...

#Toán lớp 7

1

PK

phạm khánh linh

27 tháng 7 2018

a. = 1/20 + 5 - 1/2

= 101/20 - 1/2

= 91/20

b. = ( 6/15 - 3/5) - ( 7/8 + 2/16) + 3

= -1/5 - 1 + 3

= 9/5

c. = 15/7 . ( 3/5 - 8/5)

= 15/7 . ( -1)

= - 15/7

e. = -14/9 - 3/9

= -17/9

f. = 19/21 . ( 15/17 + 2/17) + 13/21

= 19/21 . 1 + 13/21

= 32/21

g. = 43/12 : 2 + 5/24

= 43/24 + 5/24

= 2

1/Thực hiện phép tính:𝒂) ( \(\dfrac{7}{5}\) − \(\dfrac{8}{7}\) ) + \(3\dfrac{2}{5}\) ∶ 𝟎,𝟔b) \(\dfrac{11}{6}\) + \(\dfrac{7}{6}\) ∶ \(\dfrac{-5}{4}\)c) \(\dfrac{7}{4}\) − \(\dfrac{5}{4}\) . \(\dfrac{8}{15}\)2/ Tìm x biếtb) 𝒙 + 𝟐,𝟓 = \(\dfrac{-8}{3}\)b) 𝟐𝒙 − 𝟐𝟎% = \(\dfrac{9}{5}\)𝒄) ( \(\dfrac{5}{4}\) )2 + 𝒙 =...

C

Cihce

25 tháng 10 2021

#Toán lớp 7

1

VV

Vân Vui Vẻ

25 tháng 10 2021

\(1\)/

\(a\)) \(=\left(\dfrac{7}{5}-\dfrac{8}{7}\right)+\dfrac{17}{5}:0,6\)

\(=\dfrac{9}{35}+\dfrac{17}{3}\)

\(=\dfrac{622}{105}\)

\(b\)) \(=\dfrac{11}{6}+\dfrac{-14}{15}\)

\(=\dfrac{9}{10}\)

\(c\)/ \(=\dfrac{7}{4}-\dfrac{2}{3}\)

\(=\dfrac{13}{12}\)

Bài 1: Thực hiện phép tính A, \(\dfrac{-8}{15}\)+\(\dfrac{13}{30}\)-\(\dfrac{5}{12}\) B, \(\dfrac{3}{2}\).\(\dfrac{7}{2}\)+(\(\dfrac{-5}{6}\)+\(\dfrac{1}{10}\):\(\dfrac{11}{30}\) ...

BT

Bành Thị Kem Trộn

21 tháng 3 2022

1

VD

Vô danh

21 tháng 3 2022

\(a,\dfrac{-8}{15}+\dfrac{13}{30}-\dfrac{5}{12}=\dfrac{-32}{60}+\dfrac{26}{60}-\dfrac{25}{60}=-\dfrac{31}{60}\\ b,\dfrac{3}{2}.\dfrac{7}{2}+\left(\dfrac{-5}{6}+\dfrac{1}{10}:\dfrac{11}{30}\right)=\dfrac{21}{4}+\left(\dfrac{-5}{6}+\dfrac{3}{11}\right)=\dfrac{21}{4}+\dfrac{-37}{66}=\dfrac{619}{132}\)

\(c,\dfrac{-20}{21}.\dfrac{22}{35}+\dfrac{-20}{21}.\dfrac{13}{35}+\dfrac{-22}{21}=\dfrac{-20}{21}\left(\dfrac{22}{35}+\dfrac{13}{35}\right)+\dfrac{-22}{21}=\dfrac{-20}{21}.1+\dfrac{-22}{21}=\dfrac{-20}{21}+\dfrac{-22}{21}=\dfrac{-42}{21}=-2\)

Thực hiện phép tính: a) \(11\dfrac{3}{4}-\left(6\dfrac{5}{6}-4\dfrac{1}{2}\right)+1\dfrac{2}{3}\) b) \(2\dfrac{17}{20}-1\dfrac{11}{15}+6\dfrac{9}{20}:3\) ...

TT

Trần Thị Thảo

21 tháng 4 2022

1

NL

Nguyễn Lê Phước Thịnh

27 tháng 6 2023

a: =11+3/4-6-5/6+4+1/2+1+2/3

=10+9/12-10/12+6/12+8/12

=10+13/12=133/12

b: \(=2+\dfrac{17}{20}-1-\dfrac{11}{15}+2+\dfrac{3}{20}\)

=3-11/15

=34/15

c: \(=\dfrac{31}{7}:\left(\dfrac{7}{5}\cdot\dfrac{31}{7}\right)\)

\(=\dfrac{31}{7}:\dfrac{31}{5}=\dfrac{5}{7}\)

d: \(=\dfrac{29}{8}\cdot\dfrac{36}{29}\cdot\dfrac{15}{23}\cdot\dfrac{23}{5}=\dfrac{9}{2}\cdot3=\dfrac{27}{2}\)

PL

Phạm Lê Bảo Châu

21 tháng 4 2022

Câu 1: Thực hiện phép tính
a, \(\dfrac{7}{9}-\dfrac{16}{9}\)

b, \(\dfrac{2}{-15}+\dfrac{7}{10}\)

c, \(\left(4\dfrac{2}{3}-4\dfrac{3}{4}\right):\dfrac{-5}{12}-\dfrac{4}{5}\)

d, \(\dfrac{-141}{157}.\dfrac{23}{59}-\dfrac{141}{157}.\dfrac{36}{59}+\dfrac{16}{-157}\)

1

N

NguyetThienn

21 tháng 4 2022

a. 7/9 - 16/9 = -9/9 = -1

b. 2/-15 + 7/10 = 17/30

c. (4 2/3 - 4 3/4) : -5/12 - 4/5

= (14/3 - 19/4) : (-5/12) - 4/5

= -1/12 : (-5/12) - 4/5

= 1/5 - 4/5

= -3/5

PL

Phạm Lê Bảo Châu

21 tháng 4 2022

thanks

Thực hiện các phép tính sau: (từng bước)c)\(\dfrac{11}{10}\) - \(\dfrac{-7}{24}\) =e)\(\dfrac{-8}{3}\) . \(\dfrac{15}{7}\) =f)\(\dfrac{-2}{5}\) . 4\(\dfrac{1}{2}\) =g) \(\dfrac{5}{3}\) : \(\dfrac{5}{-3}\) =h) \(\dfrac{5}{4}\) :...

Q3

Quỳnhh-34- 6.5 Phạm như

20 tháng 4 2022

1

O

★彡✿ทợท彡★

20 tháng 4 2022

c) \(\dfrac{11}{10}-\dfrac{-7}{24}=\dfrac{11}{10}+\dfrac{7}{24}=\dfrac{167}{120}\)

e) \(\dfrac{-8}{3}\cdot\dfrac{15}{7}=\dfrac{-120}{21}=\dfrac{-40}{7}\)

f) \(\dfrac{-2}{5}\cdot4\dfrac{1}{2}=\dfrac{-2}{5}\cdot\dfrac{9}{2}=-\dfrac{9}{5}\)

g) \(\dfrac{5}{3}:\dfrac{5}{-3}=\dfrac{5}{3}:\dfrac{-5}{3}=\dfrac{5}{3}\cdot\dfrac{-3}{5}=-1\)

h) \(\dfrac{5}{4}:\left(-9\right)=\dfrac{5}{4}:\dfrac{-9}{1}=\dfrac{5}{4}\cdot\dfrac{-1}{9}=-\dfrac{5}{36}\)

1. Thực hiện phép tính A=3.\(\dfrac{1}{1\cdot2}\)- 5.\(\dfrac{1}{2\cdot3}\)+7.\(\dfrac{1}{3\cdot4}\)- ... +15\(\dfrac{1}{7\cdot8}\)-17\(\dfrac{1}{8\cdot9}\) 2.Tính tỉ số \(\dfrac{A}{B}\) biết A=\(\dfrac{1}{1\cdot300}\)+\(\dfrac{1}{2\cdot301}\)+\(\dfrac{1}{3\cdot302}\)+...+\(\dfrac{1}{101\cdot400}\) và B=\(\dfrac{1}{1\cdot102}\)+\(\dfrac{1}{2\cdot103}\)+\(\dfrac{1}{3\cdot104}\)+...+\(\dfrac{1}{299\cdot400}\) Nhanh lên nhé, vội lắm...

VN

Vũ Nguyên Trần Thế

17 tháng 10 2023

Thực hiện các phép tính:\(a,\left(\dfrac{7}{16}+\dfrac{-1}{8}+\dfrac{9}{32}\right):\dfrac{5}{4}\) \(b,10\dfrac{2}{9}+2\dfrac{3}{5}+6\dfrac{2}{9}\)\(c,30\%-2\dfrac{2}{5}+0,2.\dfrac{1}{2}\) ...

0

KJ

❖ Khang/GD❄ 『ʈєɑɱ❖Hoàng๖ۣۜGia☆』

26 tháng 2 2022

Bài 1: Thực hiện phép tính: a, \(\left(\dfrac{7}{20}+\dfrac{11}{15}-\dfrac{15}{12}\right):\left(\dfrac{11}{20}-\dfrac{26}{45}\right)\) b, \(\dfrac{5-\dfrac{5}{3}+\dfrac{5}{9}-\dfrac{5}{27}}{8-\dfrac{8}{3}+\dfrac{8}{9}-\dfrac{8}{27}}:\dfrac{15-\dfrac{15}{11}+\dfrac{15}{121}}{16-\dfrac{16}{11}+\dfrac{16}{121}}\) c,...

2

NL

Nguyễn Lê Phước Thịnh

26 tháng 2 2022

a: \(=\dfrac{14-2+9}{32}\cdot\dfrac{4}{5}=\dfrac{21}{5}\cdot\dfrac{1}{8}=\dfrac{21}{40}\)

b: \(=10+\dfrac{2}{9}+2+\dfrac{3}{5}+6+\dfrac{2}{9}=18+\dfrac{47}{45}=\dfrac{857}{45}\)

c: \(=\dfrac{3}{10}-\dfrac{12}{5}+\dfrac{1}{10}=\dfrac{4}{10}-\dfrac{12}{5}=\dfrac{2}{5}-\dfrac{12}{5}=-2\)

d: \(=\dfrac{-25}{30}\left(\dfrac{37}{44}+\dfrac{13}{44}-\dfrac{6}{44}\right)=\dfrac{-25}{30}\cdot1=-\dfrac{5}{6}\)

Đúng(2)

NA

Nguyễn acc 2

26 tháng 2 2022

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Đúng(2)

DH

Đặng Hoài An

17 tháng 4 2017

1

NN

Nam Nguyễn

9 tháng 6 2017

\(a,\left(\dfrac{7}{20}+\dfrac{11}{15}-\dfrac{15}{12}\right):\left(\dfrac{11}{20}-\dfrac{26}{45}\right).\)

\(=\left(\dfrac{21}{60}+\dfrac{44}{60}-\dfrac{75}{60}\right):\left(\dfrac{99}{180}-\dfrac{104}{180}\right).\)

\(=\left(\dfrac{65}{60}-\dfrac{75}{60}\right):\left(-\dfrac{5}{180}\right).\)

\(=-\dfrac{10}{60}:\left(-\dfrac{5}{180}\right).\)

\(=-\dfrac{1}{6}:\left(-\dfrac{1}{36}\right).\)

\(=-\dfrac{1}{6}.\left(-36\right).\)

\(=\dfrac{-1.\left(-36\right)}{6}=\dfrac{36}{6}=6.\)

Vậy......

\(b,\dfrac{5-\dfrac{5}{3}+\dfrac{5}{9}-\dfrac{5}{27}}{8-\dfrac{8}{3}+\dfrac{8}{9}-\dfrac{8}{27}}:\dfrac{15-\dfrac{15}{11}+\dfrac{15}{121}}{16-\dfrac{16}{11}+\dfrac{16}{121}}.\)

\(=\dfrac{5\left(1-\dfrac{1}{3}+\dfrac{1}{9}-\dfrac{1}{27}\right)}{8\left(1-\dfrac{1}{3}+\dfrac{1}{9}-\dfrac{1}{27}\right)}:\dfrac{15\left(1-\dfrac{1}{11}+\dfrac{1}{121}\right)}{16\left(1-\dfrac{1}{11}+\dfrac{1}{121}\right)}.\)

\(=\dfrac{5}{8}:\dfrac{15}{16}.\)

\(=\dfrac{5}{8}.\dfrac{16}{15}=\dfrac{5.16}{8.15}=\dfrac{1.2}{1.3}=\dfrac{2}{3}.\)

Vậy......

c, (làm tương tự câu b).

~ Học tốt!!! ~

Thực hiện phép tính: a) \(\dfrac{8}{13}\) + \(\dfrac{5}{13}\) b)\(\dfrac{2}{3}\) + \(\dfrac{-2}{5}\) + \(\dfrac{-5}{6}\) - \(\dfrac{13}{10}\) c) -\(\dfrac{2}{7}\) - (\(\dfrac{5}{11}\) - \(\dfrac{9}{7}\)) + \(\dfrac{5}{11}\) d) \(\dfrac{-3}{7}\) x \(\dfrac{-1}{9}\) + \(\dfrac{7}{-18}\) x \(\dfrac{-3}{7}\) + \(\dfrac{5}{6}\) x \(\dfrac{-3}{7}\) e) \(11\dfrac{1}{4}\) - (\(2\dfrac{5}{7}\) + \(5\dfrac{1}{4}\)) f) (\(8\dfrac{5}{11}\) + \(3\dfrac{5}{8}\)) - \(3\dfrac{5}{11}\) g)...

NP

Nguyễn Phương Anh

17 tháng 4 2023