a)\(\frac{\frac{51}{2}}{\frac{13}{2}}\)=\(\frac{51}{13}\)
b)\(-\frac{5}{\frac{15}{32}}:\frac{\frac{23}{52}}{\frac{8}{3}}=-\frac{13312}{207}\)
a)\(\frac{\frac{51}{2}}{\frac{13}{2}}\)=\(\frac{51}{13}\)
b)\(-\frac{5}{\frac{15}{32}}:\frac{\frac{23}{52}}{\frac{8}{3}}=-\frac{13312}{207}\)
tìm x
1, \(0,4\cdot x-\frac{1}{5}x=\frac{3}{4}\)
2, \(x\div1\frac{2}{7}=-3,5\)\
3, \(\left(\frac{2x}{5}-2\right)\div\left(-5\right)=\frac{3}{7}\)
4, x+ 20% x = -4,8
5, \(x-15\%x=-2\frac{11}{20}\)
6, \(\left(x\cdot25\%-\frac{2}{3}\right)\div2\frac{1}{3}=1\frac{5}{8}\)
\(\left(2\frac{1}{3}+3,5\right)\div\left(-4\frac{1}{6}+3\frac{1}{7}\right)+75\%\)\(\left(-6\frac{3}{5}\div6-8\times12,5\%-\frac{2}{15}\div0,3\right)\times\left(-0,5\right)+1\)\(\left(2\frac{1}{3}+3\frac{1}{2}\right)\div\left(-4\frac{1}{6}+3\frac{1}{7}\right)+2\frac{15}{43}\)
a) Tính giá trị của mỗi biểu thức sau :
\(\frac{3}{7}\div1;\frac{3}{7}\div\frac{2}{5};\frac{3}{7}\div\frac{5}{4}\)
b)So sánh số chia với 1 trong mỗi trường hợp trên
c) So sánh giá trị tìm được với số bị chia rồi rút ra kết luận
\(\frac{1}{2}-\frac{2}{3}+\frac{3}{4}-\frac{4}{5}-\left(\frac{-5}{6}\right)-\frac{6}{7}-\frac{-7}{8}+\frac{6}{7}-\frac{5}{6}+\frac{4}{5}-\frac{3}{4}+\frac{2}{3}-\frac{1}{2}\)
Tính hợp lý
\(\frac{\frac{5}{3}+\frac{5}{8}-\frac{5}{7}}{\frac{-4}{3}-\frac{-4}{8}+\frac{4}{7}}:\frac{\frac{2}{3}-\frac{1}{6}+\frac{6}{7}}{\frac{-1}{3}+\frac{1}{6}-\frac{1}{7}}\)
\(\frac{-5}{18}+\frac{5}{9}-\frac{11}{36}\)
\(\frac{-39}{44}\div1\frac{2}{11}\)
\(\frac{-7}{11}.\frac{11}{19}+\frac{-7}{11}.\frac{8}{19}+\frac{-4}{11}\)
Tính nhanh: \(\frac{3}{1!+2!+3!}+\frac{4}{2!+3!+4!}+\frac{5}{3!+4!+5!}+\frac{6}{4!+5!+6!}+\frac{7}{5!+6!+7!}+\frac{8}{6!+7!+8!}\)
Tính
a) \(\frac{1}{5}+\frac{-1}{6}+\frac{1}{7}+\frac{1}{-8}+\frac{1}{9}+\frac{1}{8}+\frac{1}{-7}+\frac{-1}{6}+\frac{-1}{5}\)
b) (-11).36-64.11
c) \(\frac{\frac{1}{3}+\frac{1}{7}+\frac{1}{13}}{\frac{2}{3}+\frac{2}{7}+\frac{2}{13}}.\frac{\frac{3}{4}+\frac{3}{16}+\frac{3}{64}+\frac{3}{256}}{1+\frac{1}{4}+\frac{1}{16}+\frac{1}{64}}+\frac{3}{8}\)
Thực hiện phép tính hợp lí nếu có thể:
a/ \(\frac{6}{7}+\frac{1}{7}\cdot\frac{2}{7}+\frac{1}{7}\cdot\frac{5}{7}\)
b/\(\frac{2}{3}\cdot\frac{5}{7}\cdot\frac{-3}{8}\cdot\frac{11}{5}\)
c/\(11\frac{4}{7}-\left(2\frac{3}{5}+5\frac{4}{7}\right)\)
d/\(\frac{3}{4}-\frac{3}{4}\cdot\left(\frac{2}{3}+1\right)\)
e/\(0.5\cdot1\frac{1}{3}\cdot75\%:\frac{2}{5}+\frac{3}{5}\)
f/\(\frac{6}{7}+\frac{5}{8}:5-\frac{3}{16}\cdot\left(-2\right)^2\)
g/\(1\frac{3}{8}+\left(\frac{-5}{6}+\frac{7}{12}\right):\frac{2}{3}\)
h/\(1\frac{1}{4}\cdot\frac{-3}{2}+50\%\cdot98\)
i/\(\left(2,09:1,1+4,5\right)\cdot\frac{5}{8}+4,32\)