K
Khách

Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.

18 tháng 2 2019

3/2 là phần phải k bạn

18 tháng 2 2019

a. = 3/2 + (2/3 + 4/3)

    = 3/2 + 6/3

    = 3/2 + 2

    = 3/2 + 4/2

    = 7/2

b. = 3/5 + 7/5 + 3/4

    = 10/5 + 3/4

    = 2 + 3/4

    = 8/4 + 3/4

    = 11/4

19 tháng 3 2017

a, \(\frac{3}{2}\)\(\frac{2}{3}\) + \(\frac{4}{3}\)

\(\frac{3}{2}\)+ ( \(\frac{2}{3}\)\(\frac{4}{3}\))

\(\frac{3}{2}\)\(2\)

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

b, \(\frac{3}{5}\)\(\frac{7}{5}\)\(\frac{3}{4}\)

= (\(\frac{3}{5}\)\(\frac{7}{5}\)) + \(\frac{3}{4}\)

\(2\)\(\frac{3}{4}\)

\(\frac{11}{4}\)

15 tháng 2 2017

\(a,\frac{12}{25}+\frac{3}{5}+\frac{13}{25}\)

\(=\left(\frac{12}{25}+\frac{13}{25}\right)+\frac{3}{5}\)

\(=\frac{25}{25}+\frac{3}{5}\)

\(=1+\frac{3}{5}\)

\(=\frac{8}{5}\)

\(b,\frac{3}{2}+\frac{2}{3}+\frac{4}{3}\)

\(=\frac{3}{2}+\left(\frac{2}{3}+\frac{4}{3}\right)\)

\(=\frac{3}{2}+2\)

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

\(c,\frac{3}{5}+\frac{7}{5}+\frac{3}{4}\)

\(=\left(\frac{3}{5}+\frac{7}{5}\right)+\frac{3}{4}\)

\(=2+\frac{3}{4}\)

\(=\frac{11}{4}\)

26 tháng 2 2019

A,  4/9 + [3/8 + 5/8 ]

    =4/9 + 1

    =13/9

B,  [3/7+4/7]+2/3

=1+2/3

=5/3

26 tháng 2 2019

\(a)\frac{4}{9}+\frac{3}{8}+\frac{5}{8}=\frac{4}{9}+(\frac{3}{8}+\frac{5}{8})=\frac{4}{9}+1=\frac{4+9}{9}=\frac{13}{9}\)

\(b)\frac{3}{7}+\frac{2}{3}+\frac{4}{7}=(\frac{3}{7}+\frac{4}{7})+\frac{2}{3}=1+\frac{2}{3}=\frac{3+2}{3}=\frac{5}{3}\)

19 tháng 2 2017

a. 12/25 + 3 / 5+ 13/25 = ( 12/25+13/25)+3/5 = 1 + 3/5= 8/5

b. 3/2 + 2/3 + 4/3 = 3/2+( 2/3+4/3)= 3/2 + 2=7/2

c.3/5+7/5+3/4= (3/5+7/5)+3/4 = 2+ 3/4=11/4 

chúc bn hc tốt 

19 tháng 2 2017

a. 12/25+3/5+13/25

=1+3/5

=8/5

b.3/2+2/3+4/3

=3/2+2

=7/2

c.3/5+7/5+3/4

=2+3/4

=11/4

14 tháng 2 2018

a) \(\frac{12}{25}+\frac{3}{5}+\frac{134}{25}=\left(\frac{12}{25}+\frac{134}{25}\right)+\frac{3}{5}=\frac{146}{25}+\frac{3}{5}=\frac{146}{25}+\frac{15}{25}=\frac{161}{25}\)

b) \(\frac{3}{2}+\frac{2}{3}+\frac{4}{3}=\frac{3}{2}+\left(\frac{2}{3}+\frac{4}{3}\right)=\frac{3}{2}+\frac{6}{3}=\frac{9}{6}+\frac{12}{6}=\frac{21}{6}=\frac{7}{2}\)

c) \(\frac{3}{5}+\frac{7}{5}+\frac{3}{4}=\left(\frac{3}{5}+\frac{7}{5}\right)+\frac{3}{4}=\frac{10}{5}+\frac{3}{4}=2+\frac{3}{4}=\frac{8}{4}+\frac{3}{4}=\frac{11}{4}\)

14 tháng 2 2018

a,\(\frac{12}{25}+\frac{3}{5}+\frac{134}{25}=\frac{12}{25}+\frac{15}{25}+\frac{134}{25}=\frac{161}{25}\)

b, \(\frac{3}{2}+\frac{2}{3}+\frac{4}{3}=\frac{3}{2}+\left(\frac{2}{3}+\frac{4}{3}\right)=\frac{3}{2}+\frac{6}{3}=\frac{3}{2}+2=\frac{7}{2}\)

c, \(\left(\frac{3}{5}+\frac{7}{5}\right)+\frac{3}{4}=\frac{10}{5}+\frac{3}{4}=2+\frac{3}{4}=\frac{11}{4}\)

15 tháng 2 2018

\(\frac{9}{10}\)+\(\frac{7}{9}\)+\(\frac{5}{8}\)+\(\frac{3}{7}+\frac{3}{5}+\frac{2}{5}+\frac{4}{7}+\frac{3}{8}+\frac{2}{9}+\frac{1}{10}\)

\(=\left(\frac{9}{10}+\frac{1}{10}\right)+\left(\frac{7}{9}+\frac{2}{9}\right)+\left(\frac{5}{8}+\frac{3}{8}\right)\)\(+\left(\frac{3}{7}+\frac{4}{7}\right)+\left(\frac{3}{5}+\frac{2}{5}\right)\)

\(=1+1+1+1+1\)

\(=5\)

15 tháng 2 2018

9/10 + 7/9 + 5/8 + 3/7 + 3/5 + 2/5 + 4/7 + 3/8 + 2/9 + 1/10

= ( 9/10 + 1/10 ) + ( 7/9 + 2/9 ) + ( 5/8 + 3/8 ) + ( 3/7 + 4/7 ) + ( 3/5 + 2/5 )

= 1 + 1 + 1 + 1 + 1

= 5

15 tháng 2 2018

\(\frac{9}{10}+\frac{7}{9}+\frac{5}{8}+\frac{3}{7}+\frac{3}{5}+\frac{2}{5}+\frac{4}{7}+\frac{3}{8}+\frac{2}{9}+\frac{1}{10}\)

\(\left(\frac{9}{10}+\frac{1}{10}\right)+\left(\frac{7}{9}+\frac{2}{9}\right)+\left(\frac{5}{8}+\frac{3}{8}\right)+\left(\frac{3}{7}+\frac{4}{7}\right)+\left(\frac{3}{5}+\frac{2}{5}\right)\)

\(\frac{10}{10}+\frac{9}{9}+\frac{8}{8}+\frac{7}{7}+\frac{5}{5}\)

\(1+1+1+1+1\)

\(1\times5\)

\(5\)

15 tháng 2 2018

Gọi A là tổng của 9/10 + 7/9 + 5/8 + 3/7 + 3/5 + 2/5 + 4/7 + 3/8 + 2/9 + 1/10, ta có :

A = 9/10 + 7/9 + 5/8 + 3/7 + 3/5 + 2/5 + 4/7 + 3/8 + 2/9 + 1/10

A = (9/10 + 1/10) + (7/9 + 2/9) + (5/8 + 3/8) + (3/7 + 4/7) + (3/5 + 2/5)

A = 1 + 1 + 1 + 1 + 1

A = 5

15 tháng 2 2018

\(\frac{9}{10}+\frac{7}{9}+\frac{5}{8}+\frac{3}{7}+\frac{3}{5}+\frac{2}{5}+\frac{4}{7}+\frac{3}{8}+\frac{2}{9}+\frac{1}{10}\)\(=\frac{9}{10}+\frac{1}{10}+\frac{7}{9}+\frac{2}{9}+\frac{5}{8}+\frac{3}{8}+\frac{3}{7}+\frac{4}{7}+\frac{3}{5}+\frac{2}{5}\)

\(=\left[\frac{9}{10}+\frac{1}{10}\right]+\left[\frac{7}{9}+\frac{2}{9}\right]+\left[\frac{5}{8}+\frac{3}{8}\right]+\left[\frac{3}{7}+\frac{4}{7}\right]+\left[\frac{3}{5}+\frac{2}{5}\right]\)

\(=1+1+1+1+1\)

   \(=5\)

16 tháng 2 2018

\(\frac{9}{10}+\frac{7}{9}+\frac{5}{8}+\frac{3}{7}+\frac{3}{5}+\frac{2}{5}+\frac{4}{7}+\frac{3}{8}+\frac{2}{9}+\frac{1}{10}\)

\(\left(\frac{9}{10}+\frac{1}{10}\right)+\left(\frac{7}{9}+\frac{2}{9}\right)+\left(\frac{5}{8}+\frac{3}{8}\right)+\left(\frac{3}{7}+\frac{4}{7}\right)+\left(\frac{3}{5}+\frac{2}{5}\right)\)

= 1 + 1 + 1 + 1 + 1

= 5