\(\dfrac{3-\dfrac{3}{20}+\dfrac{3}{12}-\dfrac{3}{2013}}{7-\dfrac{7}{20}+\dfrac{7}{13}-\dfrac{7}{2013}}\)
\(=\dfrac{3\left(\dfrac{1}{20}+\dfrac{1}{12}-\dfrac{1}{2013}\right)}{7\left(\dfrac{1}{20}+\dfrac{1}{12}-\dfrac{1}{2013}\right)}\)
\(=\dfrac{3}{7}\)
Tính thuận tiện A=\(\dfrac{3}{2}-\dfrac{5}{6}+\dfrac{7}{12}-\dfrac{9}{20}+\dfrac{11}{30}-\dfrac{13}{42}+\dfrac{15}{56}-\dfrac{17}{72}\)
a) \(\left(7\dfrac{4}{9}+3\dfrac{7}{11}\right)-3\dfrac{4}{9}\)
b) \(5\dfrac{2}{7}\cdot\dfrac{8}{11}+5\dfrac{2}{7}\cdot\dfrac{5}{11}-5\dfrac{2}{7}\cdot\dfrac{2}{11}\)
c) \(1\dfrac{13}{15}\cdot0,75-\left(\dfrac{11}{20}+25\%\right):\dfrac{7}{5}\)
Giúp mình nha
Đang cần gấp
P=\(\dfrac{20+\dfrac{19}{13}+\dfrac{19}{101}}{7+\dfrac{7}{13}+\dfrac{7}{19}+\dfrac{7}{101}}\)
Tính:
\(\dfrac{7}{13}.\dfrac{5}{19}+\dfrac{7}{19}.\dfrac{8}{13}-3.\dfrac{7}{19}\)
\(\dfrac{6}{13}\) x \(\dfrac{8}{7}\) + \(\dfrac{6}{13}\) x \(\dfrac{9}{7}\) - \(\dfrac{3}{13}\) x \(\dfrac{6}{7}\)
Help me please
Tính nhanh :
\(A=\dfrac{24.47-23}{24+47-23}.\dfrac{3+\dfrac{3}{7}-\dfrac{3}{11}+\dfrac{3}{1001}-\dfrac{3}{13}}{\dfrac{9}{1001}-\dfrac{9}{13}+\dfrac{9}{7}-\dfrac{9}{11}+9}\)
Chứng minh rằng: \(\dfrac{3}{2^2}+\dfrac{5}{6^2}+\dfrac{7}{12^2}+\dfrac{9}{20^2}+...+\dfrac{19}{90^2}< 1\)
\(\text{Thực hiện phép tính một cách hợp lý nhất (nếu có thể):}\)
\(1\)) \(\left(\dfrac{-8}{13}:\dfrac{3}{7}+\dfrac{-5}{13}:\dfrac{3}{7}\right).\dfrac{\left(-4\right)^3.\left|-3\right|}{7}\)
\(2\)) \(75\)\(\text{%}\)\(-\left(\dfrac{5}{2}+\dfrac{5}{3}\right)+\left(-\dfrac{1}{2}\right)^2\)
\(\dfrac{\dfrac{3}{7}-\dfrac{3}{11}+\dfrac{3}{13}}{\dfrac{5}{7}-\dfrac{5}{11}+\dfrac{5}{13}}+\dfrac{\dfrac{1}{2}-\dfrac{1}{3}+\dfrac{1}{4}}{\dfrac{5}{4}-\dfrac{5}{6}+\dfrac{5}{8}}\)
THỰC HIỆN PHÉP TÍNH NHA MN
