mik nhầm nha mn

\(1-\left\{5\frac{4}{9}+x-7\frac{7}{18}\right\}:15\frac{3}{4}=0\)

           Bài làm :

Ta có :

\(...\)

\(\left\{5-\frac{4}{9}+x-7\frac{7}{18}\right\}\div15\frac{3}{4}=1\)

\(5-\frac{4}{9}+x-7\frac{7}{18}=15\frac{3}{4}\)

\(x-\frac{17}{6}=15\frac{3}{4}\)

\(x=15\frac{3}{4}+\frac{17}{6}=\frac{223}{12}\)

Vậy x=223/12

           Bài làm khi sửa lại đề :

Ta có :

\(1-\left\{5\frac{4}{9}+x-7\frac{7}{18}\right\}\div15\frac{3}{4}=0\)

\(\left\{5\frac{4}{9}+x-7\frac{7}{18}\right\}\div15\frac{3}{4}=1\)

\(x-\frac{35}{18}=15\frac{3}{4}\)

\(x=15\frac{3}{4}+\frac{35}{18}=\frac{637}{36}\)

Vậy x=637/36

x=17,69444444    

cái này mk làm r!!!

a) x = 99/20

b) x = 7

c) x = 2

( chỉ lm đc đến đó thui nk )

khỏi chép lại đề nha

\(1-\left(\frac{49}{9}+x-\frac{133}{18}\right):15=0+\frac{3}{4}\)

\(1-\left(\frac{49}{9}+x-\frac{133}{18}\right):15=\frac{3}{4}\)

\(1-\left(\frac{49}{9}+x-\frac{133}{18}\right)=\frac{3}{4}.15\)

\(1-\left(\frac{49}{9}+x-\frac{133}{18}\right)=\frac{45}{4}\)

\(\frac{49}{9}+x-\frac{133}{18}=1-\frac{45}{4}\)

\(\frac{49}{9}+x-\frac{133}{18}=\frac{-41}{4}\)

\(\frac{49}{9}+x=\frac{-41}{4}+\frac{133}{18}\)

\(\frac{49}{9}+x=\frac{-103}{36}\)

\(x=\frac{-103}{3}-\frac{49}{9}\)

\(x=\frac{-299}{36}\)

tk mik nha

a) $\frac{1}{6}:\frac{3}{7} = \frac{1}{6} \times \frac{7}{3} = \frac{7}{{18}}$  

b) $\frac{5}{{12}}:\frac{1}{4} = \frac{5}{{12}} \times \frac{4}{1} = \frac{{5 \times 4}}{{12 \times 1}} = \frac{{5 \times 4}}{{4 \times 3 \times 1}} = \frac{5}{3}$

c) $\frac{4}{{15}}:\frac{8}{3} = \frac{4}{{15}} \times \frac{3}{8} = \frac{{4 \times 3}}{{15 \times 8}} = \frac{{4 \times 3}}{{5 \times 3 \times 4 \times 2}} = \frac{1}{{10}}$          

d) $\frac{{18}}{5}:\frac{9}{{10}} = \frac{{18}}{5} \times \frac{{10}}{9} = \frac{{18 \times 10}}{{5 \times 9}} = \frac{{9 \times 2 \times 5 \times 2}}{{5 \times 9}} = 4$

Ta có:

\(\left(\right. \frac{13 \frac{2}{9} - 15 \frac{2}{3}}{18 \frac{3}{7} - 17 \frac{1}{4}} \cdot \frac{30^{2} - 5^{4}}{25 - 12 \cdot 5^{2}} \left.\right) \cdot x = \frac{\frac{2}{11} + \frac{3}{13} + \frac{4}{15} + \frac{5}{17}}{4 \frac{1}{11} + \frac{5}{13} + \frac{9}{15} + \frac{13}{17}}\)

Bước 1: Đổi hỗn số về phân số

Bước 2: Tính toán từng phần

Ta có:

\(\frac{119}{9} - \frac{47}{3} = \frac{119 - 141}{9} = \frac{- 22}{9}\) \(\frac{129}{7} - \frac{69}{4} = \frac{516 - 483}{28} = \frac{33}{28}\) \(30^{2} - 5^{4} = 900 - 625 = 275\) \(25 - 12 \cdot 25 = 25 - 300 = - 275\)

Khi đó:

\(\left(\right. \frac{- 22}{9} \div \frac{33}{28} \cdot \frac{275}{- 275} \left.\right) = \left(\right. \frac{- 22}{9} \cdot \frac{28}{33} \cdot \left(\right. - 1 \left.\right) \left.\right) = \frac{616}{297}\)

Bước 3: Tính vế phải

Tử số:

\(\frac{2}{11} + \frac{3}{13} + \frac{4}{15} + \frac{5}{17} = \frac{35494}{36465}\)

Mẫu số:

\(4 \frac{1}{11} + \frac{5}{13} + \frac{9}{15} + \frac{13}{17} = \frac{149645}{36465}\)

→ Vế phải:

\(\frac{35494}{36465} \div \frac{149645}{36465} = \frac{35494}{149645}\)

Bước 4: Giải phương trình

\(\frac{616}{297} \cdot x = \frac{35494}{149645} \Rightarrow x = \frac{35494}{149645} \cdot \frac{297}{616} = \frac{813}{7118}\)

Vậy:

\(\boxed{x = \frac{813}{7118}}\)

hỉu không =]]]