5và 3/8-1 và 5/6

\(\frac{11}{9}-\frac67\)

\(=\frac{77}{63}-\frac{54}{63}=\frac{77-54}{63}=\frac{23}{63}\)

\(\frac{7}{10}-\frac25=\frac{7}{10}-\frac{4}{10}=\frac{7-4}{10}=\frac{3}{10}\)

\(\frac72-2=\frac72-\frac42=\frac{7-4}{2}=\frac32\)

\(\frac65\times\frac38=\frac{6\times3}{5\times8}=\frac{18}{40}=\frac{9}{20}\)

\(\frac25:\frac32=\frac25\times\frac23=\frac{2\times2}{5\times3}=\frac{4}{15}\)

\(5:\frac57=5\times\frac75=7\)

\(\frac73:4=\frac{7}{3\times4}=\frac{7}{12}\)

911​−76​

\(= \frac{77}{63} - \frac{54}{63} = \frac{77 - 54}{63} = \frac{23}{63}\)

\(\frac{7}{10} - \frac{2}{5} = \frac{7}{10} - \frac{4}{10} = \frac{7 - 4}{10} = \frac{3}{10}\)

\(\frac{7}{2} - 2 = \frac{7}{2} - \frac{4}{2} = \frac{7 - 4}{2} = \frac{3}{2}\)

\(\frac{6}{5} \times \frac{3}{8} = \frac{6 \times 3}{5 \times 8} = \frac{18}{40} = \frac{9}{20}\)

\(\frac{2}{5} : \frac{3}{2} = \frac{2}{5} \times \frac{2}{3} = \frac{2 \times 2}{5 \times 3} = \frac{4}{15}\)

\(5 : \frac{5}{7} = 5 \times \frac{7}{5} = 7\)

\(\frac{7}{3} : 4 = \frac{7}{3 \times 4} = \frac{7}{12}\)

\(=1x2x\frac{3}{2}x\frac{4}{3}x\frac{5}{4}x\frac{6}{5}x\frac{7}{6}x\frac{8}{7}\)

\(=\frac{1x2x3x4x5x6x7x8}{1x1x2x3x4x5x6x7}=8\)

\(1:\frac{1}{2}:\frac{2}{3}:\frac{3}{4}:\frac{4}{5}:\frac{5}{6}:\frac{6}{7}:\frac{7}{8}=8\)

chúc bn học gioi!

nhae$

hihiLê Thị Thu Hương

h@__@

Ai giải được đầu tiên mk k cho

a ) \(5\frac{3}{4}:3+2\frac{1}{4}.\frac{1}{3}-\frac{3}{8}=\frac{23}{4}:\frac{3}{1}+\frac{9}{4}.\frac{1}{3}=\frac{23}{12}+\frac{3}{4}=\frac{8}{3}\)

b ) \(\frac{3}{5}:\frac{5}{6}:\frac{6}{7}:\frac{7}{8}+\frac{7}{8}+\frac{2}{5}+\frac{23}{35}=\frac{3.6.7.8}{5.5.6.7}+\frac{7}{8}+\frac{2}{5}+\frac{23}{35}=\frac{24}{25}+\frac{7}{8}+\frac{2}{5}+\frac{23}{35}=\frac{4049}{1400}\)

a) =  \(\frac{23}{4}:3+\frac{9}{4}x\frac{1}{3}-\frac{3}{8}\)

= ....

(bn tự giải nhé, mk đã làm thành phân số cho bn r`)

b) tương tự như câu a nhé

nha bn

a) \(\frac{59}{42}\)
b) \(\frac{17}{36}\)
c) \(\frac{5}{51}\)
d) \(\frac{4}{7}\)

a: \(\frac56+\frac47=\frac{35}{42}+\frac{24}{42}=\frac{35+24}{42}=\frac{59}{42}\)

b: \(\frac54-\frac79=\frac{45}{36}-\frac{28}{36}=\frac{45-28}{36}=\frac{17}{36}\)

c: \(\frac{15}{17}\times\frac19=\frac{15\times1}{17\times9}=\frac{15}{153}=\frac{5}{51}\)

d: \(\frac37:\frac68=\frac37:\frac34=\frac37\times\frac43=\frac47\)

Bạn ơi cuối cùng là + 100 ak

Nếu + 100 thì giải thế này nha :

1/2.3 + 1/3.4 + .... + 1/98.99 + 100

= (3-2)/2.3+(4-3)/3.4+.....+(99-98)/98.99 +100

= 1/2 - 1/3 + 1/3 - 1/4 + ...... + 1/98 - 1/99 + 100

= 1/2 - 1/99 + 100 = 97/198 + 100 = 19897/198