\(1\frac{1}{2}\times1\frac{1}{3}\times1\frac{1}{4}\times1\frac{1}{5}\times...1\frac{1}{9}+2005.\)

\(=\frac{3}{2}\times\frac{4}{3}\times\frac{5}{4}\times\frac{6}{5}\times...\times\frac{10}{9}+2005\)

\(=\frac{10}{2}+2005=5+2005=2010\)

.

hó thật đáy...........

`5/6+6/7-1/6+7/3`

`=(5/6-1/6+7/3)+6/7`

`=(4/6+7/3)+6/7`

`=(2/3+7/3)+6/7`

`=9/3+6/7`

`=3+6/7`

`=21/7+6/7`

`=27/7`

a)\(\frac{4}{5}-\frac{1}{4}+\frac{3}{10}\)

\(=\frac{16}{20}-\frac{5}{20}+\frac{6}{20}\)

\(=\frac{17}{20}\)

b) \(\frac{2}{5}:\left(1-\frac{1}{10}\right)\)

\(=\frac{2}{5}:\frac{9}{10}\)

\(=\frac{4}{9}\)

c)\(\frac{7}{8}\times\frac{4}{9}+\frac{1}{14}:\frac{5}{14}\)

\(=\frac{7}{18}+\frac{1}{5}\)

\(=\frac{53}{90}\)

d)\(\frac{2}{7}\times\frac{3}{11}+\frac{2}{7}\times\frac{8}{11}\)

\(=\frac{2}{7}\times\left(\frac{3}{11}+\frac{8}{11}\right)\)

\(=\frac{2}{7}\times1=\frac{2}{7}\)

e) \(12+\left(16-11\right)\times4\)

\(=12+20=32\)

f)\(2\frac{3}{7}+1\frac{4}{7}\)

\(=\frac{17}{7}+\frac{11}{7}\)

\(=4\)

g)\(\frac{2}{3}\times\frac{4}{5}+\frac{1}{5}:\frac{9}{11}\)

\(=\frac{8}{15}+\frac{11}{45}\)

\(=\frac{7}{9}\)

h)\(\left(6,2:2+3,7\right):0,2\)

\(=\left(3,1+3,7\right):0,2\)

\(=6,8:0,2=34\)

#H

Ta có: \(4\frac{3}{5}:\frac{2}{3}+1\frac{1}{5}:\frac{2}{5}\)

\(=\frac{12}{5}.\frac{3}{2}+\frac{6}{5}.\frac{5}{2}\)

\(=\frac{18}{5}+3\)

\(=6,6\)

Vậy..........

\(4\frac{3}{5}:\frac{2}{3}+1\frac{1}{5}:\frac{2}{5}\)

= \(\frac{23}{5}:\frac{2}{3}+\frac{6}{5}:\frac{2}{5}\)

= \(\frac{23}{5}x\frac{3}{2}+\frac{6}{5}x\frac{5}{2}\)

= \(\frac{69}{10}+\frac{30}{10}\)

\(=\frac{99}{10}\)

đề như thế nào vậy?

(1 phần 3 nhân x)chia 2/3 bằng 1 và 3 phần 4 chia 2/5

so sánh à bạn?

\(3\dfrac{1}{5}=\dfrac{16}{5}=3,2\)

\(-1\dfrac{1}{4}=-\dfrac{5}{4}=-1,25\)