Tính:
3x4x7
------------
12x8x9
3x4x7
---------- =
3x10x8
Tính nhanh :
a) \(\frac{3x4x7}{5x3x4}\) b) \(\frac{2x5x6x8}{6x2x8x9}\) c) \(\frac{4x5x6}{3x10x8}\)
bài 77: tính bằng cách thuận tiện:
a) 4x25x7/5x10x21 b) 2x5x11/3x11x5
c3x4x7/12x8x9 d) 4x5x6/12x10x8
e)12/25+3/5+13/25 f) 3/2+2/3+4/3
giúp mình với
tính thuận tiện:
\(\dfrac{4}{5}+\dfrac{2}{3}+\dfrac{1}{5}+\dfrac{1}{3}\) \(\dfrac{17}{12}+\dfrac{29}{7}-\dfrac{8}{7}+\dfrac{7}{12}\) \(\dfrac{9}{15}+\dfrac{16}{7}+\dfrac{2}{5}-\dfrac{1}{7}-\dfrac{2}{14}\)
\(\dfrac{2}{5}+\dfrac{6}{9}+\dfrac{7}{4}+\dfrac{3}{5}+\dfrac{1}{3}+\dfrac{1}{4}\)
mik sẽ chỉ tick 3 bn xong trước phải chi tiết rõ ràng
\(\dfrac{3}{5}+\dfrac{a}{b}=5\) \(\dfrac{a}{b}-\dfrac{4}{7}=\dfrac{5}{6}\) \(\dfrac{2}{3}\) x \(\dfrac{a}{b}=\dfrac{3}{5}\)
\(\dfrac{a}{b}:\dfrac{2}{7}=3+\dfrac{2}{3}\) \(\dfrac{7}{5}-\dfrac{a}{b}=\dfrac{2}{5}:2\)
\(\dfrac{3}{5}:\dfrac{a}{b}=\dfrac{2}{7}\) ÉT O ÉT
Tính
a.\(\dfrac{4}{9}+\dfrac{3}{7}\) \(\dfrac{3}{4}+\dfrac{7}{24}\) \(\dfrac{1}{3}+\dfrac{2}{9}+\dfrac{4}{27}\)
b.\(\dfrac{5}{6}-\dfrac{3}{8}\) \(\dfrac{7}{15}-\dfrac{11}{30}\) \(\dfrac{2}{3}+\dfrac{1}{6}-\dfrac{7}{12}\)
c.\(\dfrac{18}{25}\times\dfrac{15}{6}\) \(\dfrac{30}{49}:\dfrac{6}{7}\) \(\dfrac{1}{2}\times\dfrac{3}{4}:\dfrac{6}{5}\)
d.\(8\times\dfrac{3}{5}:\dfrac{12}{5}\) \(4:\dfrac{9}{5}:\dfrac{10}{3}\)
3 bn đầu tiên xong mik sẽ tick
6. ÉT O ÉT
\(\dfrac{125}{90}=\dfrac{25}{...}\) / \(\dfrac{84}{91}=\dfrac{...}{13}\) / \(\dfrac{75}{...}=\dfrac{25}{15}=\dfrac{...}{3}\)
\(\dfrac{6}{7}=\dfrac{...}{21}=\dfrac{54}{...}=\dfrac{...}{126}\)
\(A=\dfrac{1+\dfrac{1}{2}+\dfrac{1}{3}+\dfrac{1}{4}+...+\dfrac{1}{9}+\dfrac{1}{10}}{\dfrac{1}{1x10}+\dfrac{1}{2x9}+\dfrac{1}{3x8}+...+\dfrac{1}{8x3}+\dfrac{1}{9x2}+\dfrac{1}{10x1}}\)