4-\(\frac{5}{7}\)=
\(\frac{1}{2}\):3=
578,97nhân307
266,22:34
Tính \(A=\frac{8\frac{3}{9}.5\frac{1}{4}+3\frac{16}{19}.5\frac{1}{4}}{\left(2\frac{14}{17}-2\frac{1}{34}\right)34};\frac{7}{24}\)
Tinh:
\(A=\frac{8\frac{3}{9}.5\frac{1}{4}+3\frac{16}{19}.5\frac{1}{4}}{\left(2\frac{14}{17}-2\frac{1}{34}\right).34}:\frac{7}{24}\)
\(A=\frac{8\frac{3}{9}.5\frac{1}{4}+3\frac{16}{19}.5\frac{1}{4}}{\left(2\frac{14}{17}-2\frac{1}{34}\right).34}:\frac{7}{24}\)
\(=\frac{5\frac{1}{4}\left(8\frac{1}{3}+3\frac{16}{19}\right)}{\left(\frac{28}{34}-\frac{1}{34}\right).34}:\frac{7}{24}\)
\(=\frac{\frac{21}{4}\left(\frac{25}{3}+\frac{73}{19}\right)}{\frac{27}{34}.34}:\frac{7}{24}\)
\(=\frac{\frac{21}{4}\left(\frac{475}{57}+\frac{219}{57}\right)}{27}:\frac{7}{24}\)
\(=\frac{\frac{21}{4}.\frac{674}{57}}{27}:\frac{7}{24}\)
\(=\frac{\frac{14154}{228}}{27}.\frac{24}{7}=\frac{\frac{339696}{228}}{189}\)
A=\(\frac{15}{34}+\frac{7}{21}+\frac{9}{34}-1\frac{15}{17}+\frac{2}{3}\)
B=\(16\frac{2}{7}:\left(-\frac{3}{5}\right)-28\frac{2}{7}:\left(-\frac{3}{5}\right)\)
C=\(25\cdot\left(-\frac{1}{3}\right)^3+\frac{1}{5}-2\cdot\left(-\frac{1}{2}\right)^2-\frac{1}{2}\)
D=\(\left(-2\right)^3\cdot\left(\frac{3}{4}-0,25\right):\left(2\frac{1}{4}-1\frac{1}{6}\right)\)
E=\(5\sqrt{16}-4\sqrt{9}+\sqrt{25}-0,3\sqrt{400}\)
F=\(\left(-\frac{3}{2}\right)^2+|-\frac{5}{6}|-1\frac{1}{2}:6\)
\(A=\frac{15}{34}+\frac{7}{21}+\frac{9}{34}-1\frac{15}{17}+\frac{2}{3}=\frac{15}{34}+\frac{7}{21}+\frac{9}{34}-\frac{64}{34}+\frac{14}{21}=\left(\frac{15}{34}+\frac{9}{34}-\frac{64}{34}\right)+\left(\frac{7}{21}+\frac{14}{21}\right)=\frac{30}{34}+\frac{21}{21}=\frac{15}{17}+1=\frac{32}{17}\)
Bài 1: Tính hợp lí nếu có thể:
a,\(13\frac{2}{7}:\frac{-8}{7}+2\frac{5}{7}:\frac{-8}{7}+\frac{4}{3}\)
b,\(\frac{5}{8}.1,31+34.\left(\frac{-1}{2}\right)^4-\frac{5}{8}.2,71\)
c,\(\frac{6^8.4^2-4^4.18^4}{27^3.8^4-3^0.2^{10}.8}\)
Bạn Hương có 27 viên bi, bạn Hiền có số bi bằng 1/3 số bi của bạn Hương. Trung bình cộng số bi của hai bạn là bao nhiêu?
10 điểm
36 viên
15 viên
30 viên
18 viên
Tính giá trị biểu thức:
A = \(\frac{15}{34}+\frac{7}{21}+\frac{9}{34}-1\frac{15}{17}+\frac{2}{3}\) B = \(16\frac{2}{7}:\left(-\frac{3}{5}\right)-28\frac{2}{7}:\left(-\frac{3}{5}\right)\)
C = 25.\(\left(-\frac{1}{3}\right)^3+\frac{1}{5}-2.\left(-\frac{1}{2}\right)^2-\frac{1}{2}\)
a: \(A=\left(\dfrac{15}{34}+\dfrac{9}{34}-1-\dfrac{15}{17}\right)+\left(\dfrac{1}{3}+\dfrac{2}{3}\right)\)
\(=\left(\dfrac{12}{17}-1-\dfrac{15}{17}\right)+1\)
\(=\dfrac{-20}{17}+1=\dfrac{-3}{17}\)
b: \(B=\dfrac{-5}{3}\cdot16\dfrac{2}{7}-\dfrac{-5}{3}\cdot28\dfrac{2}{7}\)
\(=\dfrac{-5}{3}\left(16+\dfrac{2}{7}-28-\dfrac{2}{7}\right)=\dfrac{-5}{3}\cdot\left(-12\right)=20\)
c: \(C=25\cdot\dfrac{-1}{27}+\dfrac{1}{5}-2\cdot\dfrac{1}{4}-\dfrac{1}{2}\)
\(=\dfrac{-25}{27}+\dfrac{1}{5}-1\)
\(=\dfrac{-125+27-135}{135}=\dfrac{-233}{135}\)
tính giá trị biểu thức
\(A=\frac{-378.132+189.64}{15+18+21+......+45+48}\)
\(B=1,4.\frac{15}{14}-\left(\frac{4}{5}+\frac{2}{5}\right):2\frac{1}{5}-\frac{\frac{73}{77}+\frac{73}{165}+\frac{73}{285}}{\frac{25}{24}+\frac{15}{180}+\frac{20}{285}}\)
\(C=\frac{7+\frac{7}{12}-\frac{7}{144}+\frac{7}{60}}{5+\frac{6}{12}-\frac{5}{144}}.\frac{\frac{3}{4}-\frac{3}{16}+\frac{3}{64}-\frac{3}{256}}{1-\frac{1}{4}+\frac{1}{16}-\frac{1}{34}}-\frac{1}{20}\)
A =\(\frac{15}{34}+\frac{7}{21}+\frac{9}{34}-1\frac{15}{17}+\frac{2}{3}\)
B = \(16\frac{2}{7}:\left(-\frac{3}{5}\right)-28\frac{2}{7}:\left(-\frac{3}{5}\right)\)
\(A=\frac{15}{34}+\frac{7}{21}+\frac{9}{34}-1\frac{15}{17}+\frac{2}{3}\)
\(=\frac{12}{17}+\frac{1}{3}-\frac{32}{17}+\frac{2}{3}\)
\(=-\frac{20}{17}+\frac{1}{3}+\frac{2}{3}\)
\(=-\frac{20}{17}+1\)
\(=-\frac{3}{17}\)
\(B=16\frac{2}{7}:\left(-\frac{3}{5}\right)-28\frac{2}{7}:\left(-\frac{3}{5}\right)\)
\(=\left(\frac{114}{7}-\frac{198}{7}\right):\left(-\frac{3}{5}\right)\)
\(=\left(-12\right):\left(-\frac{3}{5}\right)\)
\(=20\)
A\(=\frac{15}{34}+\frac{7}{21}+\frac{9}{34}-1\frac{15}{17}+\frac{2}{3}\)
\(=\left(\frac{15}{34}+\frac{9}{34}\right)+\left(\frac{7}{21}+\frac{2}{3}\right)-1\frac{15}{17}\)
\(=\left(\frac{14}{17}-\frac{15}{17}\right)+1-1\)
\(=-\frac{1}{17}\)
\(B=16\frac{2}{7}:\left(-\frac{3}{5}\right)-28\frac{2}{7}:\left(-\frac{3}{5}\right)\)
\(B=-\frac{3}{5}.\left(16\frac{2}{7}-28\frac{2}{7}\right)\)
\(B=-\frac{3}{5}.\left(-12\right)\)
\(B=\frac{36}{5}\)
Hoctot
A=\(\frac{15}{34}\)+ \(\frac{7}{21}\)+ \(\frac{9}{34}\)- 1\(\frac{15}{17}\)+ \(\frac{2}{3}\)
= ( \(\frac{15}{34}\)+ \(\frac{9}{34}\)) + ( \(\frac{7}{21}\)+ \(\frac{2}{3}\)) - \(\frac{32}{17}\)
= \(\frac{24}{34}\)+ ( \(\frac{7}{21}\)+ \(\frac{14}{21}\)) - \(\frac{32}{17}\)
=\(\frac{12}{17}\)+ \(\frac{21}{21}\)- \(\frac{32}{17}\)
= ( \(\frac{12}{17}\) - \(\frac{32}{17}\)) +1
=\(\frac{-20}{17}\)+ \(\frac{17}{17}\)
= \(\frac{-3}{17}\)
Tính giá trị biểu thức:
\(A=\frac{15}{34}+\frac{7}{21}+\frac{9}{34}-1\frac{15}{17}+\frac{2}{3}\) \(B=16\frac{2}{7}:\left(\frac{-3}{5}\right)-28\frac{2}{7}:\left(\frac{-3}{5}\right)\)
\(C=25.\left(\frac{-1}{3}\right)^3+\frac{1}{5}-2.\left(\frac{-1}{2}\right)^2-\frac{1}{2}\)
\(\left(0,25+\frac{-11}{9}\right)\cdot\frac{5}{34}\left(\frac{-2}{9}+7\frac{1}{4}\right)\cdot\frac{5}{34}\)
Tìm x biết : \(|2x-1|-3=\left(26+\frac{4}{2013}\right).\left(\frac{-34}{35}+\frac{2}{5}-\frac{3}{7}+1\right)\)
Giải :|2x−1|- 3 = 0
|2x−1| = -3
2x+1= -3
2x= -3 -1
2x=-4
x=-2 hoặc x= 2 (Vì loại bỏ số hạng chứa giá trị tuyệt đối. Điều này tạo ra 1 ± ở vế phải của phương trình vì |x|=±x)
\(\Rightarrow\)x= ±2