Đúng ghi Đ, sai ghi S vào chỗ chấm:
a) \(\frac{3}{7}+\frac{1}{3}x\frac{3}{7}=\frac{16}{21}x\frac{3}{7}=\frac{16}{49}\) ......
b)\(\frac{5}{9}+\frac{1}{5}x\frac{5}{6}=\frac{5}{9}x\frac{1}{6}=\frac{13}{18}\) ......
c)\(\frac{13}{9}-\frac{7}{9}:\frac{2}{3}=\frac{6}{9}:\frac{3}{2}=1\) ......
d)\(\frac{11}{8}-\frac{5}{8}:\frac{3}{4}=\frac{11}{8}-\frac{5}{8}x\frac{4}{3}=\frac{11}{8}-\frac{10}{24}=\frac{23}{24}\) ......
x+\(\frac{3}{4}=\frac{5}{3}\) \(\frac{7}{5}:x=3\)\(2-x=\frac{4}{7}\)\(\frac{5}{6}\)x \(x=\frac{4}{9}\)
bài 1 : tính phân số:
a) \(\frac{5}{7}+\frac{4}{9}=?;\frac{4}{5}-\frac{2}{3}=?;\frac{9}{11}+\frac{3}{8}=?;\frac{16}{25}-\frac{2}{5}=?\)=?
b)\(5+\frac{3}{5}=?;10-\frac{9}{16}=?;\frac{2}{3}-\left(\frac{1}{6}+\frac{1}{8}\right)=?\)
c)\(\frac{5}{7}+\frac{7}{6}=?;\frac{7}{12}+\frac{17}{18}=?;\frac{9}{8}+\frac{15}{32}=?;4+\frac{35}{45}=?\)
d)\(\frac{11}{4}-\frac{15}{16}=?;\frac{5}{6}-\frac{5}{8}=?;\frac{196}{64}-2=?;3-\frac{13}{9}=?\)
e)\(\frac{8}{5}+\frac{7}{6}+\frac{5}{9}-2=?;3-\frac{5}{6}-\frac{4}{9}+\frac{32}{24}=?\)
tính bằng hai cách
a) \(\left(\frac{6}{11}+\frac{5}{11}\right)x\frac{3}{7}\) b) \(\frac{3}{5}x\frac{7}{9}+\frac{3}{5}x\frac{2}{9}\)
c) \(\left(\frac{6}{7}-\frac{4}{7}\right):\frac{2}{5}\) d) \(\frac{8}{15}:\frac{2}{11}+\frac{7}{15}:\frac{2}{11}\)
giúp mik nha
Tính nhanh
a) \(\frac{2}{3}\div\frac{4}{9}+\frac{1}{3}\div\frac{4}{9}=\)
b) \(\frac{9}{8}\div\frac{5}{7}-\frac{1}{8}\div\frac{5}{7}=\)
c) \(\frac{2}{5}\div\frac{7}{3}-\frac{2}{5}\div\frac{1}{3}=\)
d) \(\frac{3}{7}\div\frac{7}{3}+\frac{3}{7}\div\frac{9}{4}=\)
tính nhanh
\(\frac{4}{9}x\frac{3}{7}+\frac{5}{7}x\frac{4}{9}-\frac{4}{9}x\frac{1}{7}\)
1) Tính A biết rằng :
A = \(\frac{1}{2}+\frac{1}{4}+\frac{1}{8}+\frac{1}{16}+......+\frac{1}{64}\)
2) So sánh 2 phép tính sau:
\(\frac{1+2+3+4+5+6+7}{2+3+4+5+6+7+8}\)và \(\frac{1}{2}+\frac{2}{3}+\frac{3}{4}+\frac{6}{5}+\frac{7}{6}+\frac{8}{7}\)
3) Tìm \(x\)biết:
\(\frac{x\times7}{x}=7\) \(\frac{x}{x\times6}=\frac{1}{6}\)
4) Tìm 1 phân số nếu lấy \(\frac{12}{5}\)trừ đi phân số đó rồi chia cho \(\frac{5}{7}\)thì được \(\frac{12}{5}\).
tim x biet
a\(\frac{3}{5}:\frac{7}{x}:\frac{3}{4}=\frac{8}{35}\)
b,\(x< \frac{7}{12}:\frac{4}{5}\)
1. Tính nhanh
\(\frac{1}{2}\)x \(\frac{2}{3}\)x \(\frac{3}{4}\)x\(\frac{4}{5}\)x \(\frac{5}{6}\)x\(\frac{6}{7}\)x \(\frac{6}{7}\)x \(\frac{7}{8}\)x\(\frac{8}{9}\text{ }\)x \(\frac{9}{10}\)
\(\frac{1}{2}\): \(\frac{3}{2}\): \(\frac{5}{4}\)\(\frac{6}{5}\):\(\frac{7}{6}\):\(\frac{8}{7}\)