8/11<x/13<9/11
=>8.13<11x<9.13
=>104<11x<117
=>104/11<x<117/11
Vậy 104/11<x<117/11
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Các câu hỏi tương tự
Tìm x, biết:
\(\dfrac{x-9}{11}+\dfrac{x-10}{12}+\dfrac{x-11}{13}=\dfrac{x-12}{14}+\dfrac{x-28}{15}\)
Tìm x, biết:
\(x=\dfrac{19}{11}\cdot\dfrac{5}{14}+\dfrac{1}{11}\cdot\dfrac{5}{7}-\sqrt{\dfrac{25}{4}}\cdot\dfrac{2}{11}\)
A=\(\dfrac{\dfrac{3}{4}-\dfrac{3}{11}+\dfrac{3}{13}}{\dfrac{5}{7}-\dfrac{5}{11}+\dfrac{5}{13}}+\dfrac{\dfrac{1}{2}-\dfrac{1}{3}+\dfrac{1}{4}}{\dfrac{5}{4}-\dfrac{5}{6}+\dfrac{5}{8}}\)
23 tháng 9 2021 lúc 21:33
Bài 3 tìm x;y ;z biết :
\(\dfrac{12x-15y}{7}=\dfrac{20z-12x}{9}=\dfrac{15y-20z}{11}\) và x + y + z = 48
thuc hien phep tinh
a) \(\dfrac{11}{15}.\dfrac{12}{13}+\dfrac{8}{15}+\dfrac{11}{15}.\dfrac{14}{13}\)
b)
A=\(\dfrac{\dfrac{3}{4}-\dfrac{3}{11}+\dfrac{3}{13}}{\dfrac{5}{7}-\dfrac{5}{11}+\dfrac{5}{13}}\) +\(\dfrac{\dfrac{1}{2}-\dfrac{1}{3}+\dfrac{1}{4}}{\dfrac{5}{4}-\dfrac{5}{6}+\dfrac{5}{8}}\)
\(\dfrac{\dfrac{3}{7}-\dfrac{3}{11}+\dfrac{3}{13}}{\dfrac{5}{7}-\dfrac{5}{11}+\dfrac{5}{13}}\) + \(\dfrac{\dfrac{1}{2}-\dfrac{1}{3}+\dfrac{1}{4}}{\dfrac{5}{4}+\dfrac{5}{8}-\dfrac{5}{6}}\)
Tìm x biết : \(\dfrac{x+1}{10}+\dfrac{x+1}{11}+\dfrac{x+1}{12}=\dfrac{x+1}{13}+\dfrac{x+1}{14}\)
2. thực hiện phép tính
a \(\dfrac{17}{15}:\dfrac{4}{3}\)
b.\(\dfrac{-12}{21}:\dfrac{34}{43}\)
c.\(\dfrac{-5}{9}.\dfrac{3}{11}+\dfrac{13}{18}.\dfrac{3}{11}\)
d.\(\dfrac{-2}{9}.\dfrac{5}{11}+\dfrac{-16}{9}.\dfrac{5}{11}\)