\(=25\cdot\dfrac{-1}{125}+\dfrac{1}{5}-2\cdot\dfrac{1}{4}-\dfrac{1}{2}\)
=-1/5+1/5-1/2-1/2
=-1
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Các câu hỏi tương tự
Bài 1: Thực hiện phép tính:
\(\sqrt{25}\)x\(\left(0,4-1\dfrac{1}{12}\right)\):\(\left[\left(-2\right)^3x\dfrac{11}{8}\right]\)
Tính hợp lí nếu có thể
a) \(\left(\dfrac{5}{7}-\dfrac{7}{5}\right)-\left[\dfrac{1}{2}-\left(-\dfrac{2}{7}-\dfrac{1}{10}\right)\right]\)
b) \(\dfrac{2}{15}:\left(-5\dfrac{4}{5}\right).2\dfrac{5}{12}+\sqrt{1\dfrac{9}{16}}:\left(-\dfrac{3}{4}\right)\)
2. thực hiện phép tính
a. \(\dfrac{3}{8}.72\dfrac{1}{5}-51\dfrac{1}{5}.\dfrac{3}{8}\)
b.\(25.\left(\dfrac{-1}{5}^{ }\right)^3+\dfrac{1}{5}-2.\left(\dfrac{-1}{2}\right)^2-\dfrac{1}{2}\)
c.\(35\dfrac{1}{6}.\dfrac{-4}{5}-45\dfrac{1}{6}.\dfrac{-1}{5}\)
thực hiện phép tính: \(\left(5+\dfrac{1}{5}-\dfrac{2}{9}\right)-\left(2-\dfrac{1}{23}-2\dfrac{3}{35}+\dfrac{5}{6}\right)-\left(8+\dfrac{2}{7}-\dfrac{1}{18}\right)\)
Thực hiện phép tính:
\(A=\dfrac{2^{12}.3^5-4^6.9^2}{\left(2^2.3\right)^6+8^4.3^5}-\dfrac{5^{10}.7^3-25^5.49^2}{\left(125.7\right)^3+5^9.14^3}\)
\(B=\dfrac{1-\dfrac{1}{\sqrt{49}}+\dfrac{1}{49}-\dfrac{1}{\left(7\sqrt{7}\right)^2}}{\dfrac{\sqrt{64}}{2}-\dfrac{4}{7}+\dfrac{2^2}{7^2}-\dfrac{4}{343}}\)
1 thực hiện phép tính(tính nhanh nếu có thể)
\(\left(7\dfrac{1}{3}-\dfrac{1}{3}\right):\dfrac{1}{7}\)
\(\dfrac{-1}{3}.\left(\dfrac{-15}{17}\right).\dfrac{34}{45}\) c,\(\dfrac{1}{2}.\dfrac{6}{5}-\dfrac{1}{5}.\dfrac{1}{2}\)
a,dfrac{8^{20}+4^{20}}{4^{25}+64^5}b,left(1+dfrac{2}{3}-dfrac{1}{4}right).left(dfrac{4}{5}-dfrac{3}{4}right)^2c,23dfrac{1}{3}:left(dfrac{-5}{7}right)-13dfrac{1}{3}:left(dfrac{-5}{7}right)d,1:left(dfrac{2}{3}-dfrac{3}{4}right)^2e,dfrac{45^{10}.5^{20}}{75^{15}}
Đọc tiếp
a,\(\dfrac{8^{20}+4^{20}}{4^{25}+64^5}\)
b,\(\left(1+\dfrac{2}{3}-\dfrac{1}{4}\right).\left(\dfrac{4}{5}-\dfrac{3}{4}\right)^2\)
c,\(23\dfrac{1}{3}:\left(\dfrac{-5}{7}\right)-13\dfrac{1}{3}:\left(\dfrac{-5}{7}\right)\)
d,1:\(\left(\dfrac{2}{3}-\dfrac{3}{4}\right)^2\)
e,\(\dfrac{45^{10}.5^{20}}{75^{15}}\)
Thực hiện phép tính
a, A = \(\left(\dfrac{1}{4\times9}+\dfrac{1}{9\times14}+\dfrac{1}{14\times19}+....+\dfrac{1}{44\times49}\right)\times\dfrac{1-3-5-7-....-49}{89}\)
b, B = \(\dfrac{2^{12}\times3^5-4^6\times9^2}{\left(2^2\times3\right)^6+8^4\times3^5}-\dfrac{5^{10}\times7^3-25^5\times49^2}{\left(125\times7\right)^3-5^9\times14^3}\)
Thực hiện phép tính:\(\left(-\dfrac{1}{2}\right)-\left(-\dfrac{3}{5}\right)+\left(-\dfrac{1}{9}\right)+\dfrac{1}{71}-\left(-\dfrac{2}{7}\right)+\dfrac{4}{35}-\dfrac{7}{18}\)