Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a) \(\frac{13}{19}+\frac{18}{19}+\frac{19}{19}=\left(\frac{13}{19}+\frac{17}{19}\right)+\frac{18}{19}=\frac{20}{19}+\frac{18}{19}=\frac{48}{19}\)
b) \(\frac{3}{5}+\frac{3}{16}+\frac{13}{16}=\left(\frac{3}{16}+\frac{13}{16}\right)+\frac{3}{5}=1+\frac{3}{5}=\frac{5}{5}+\frac{3}{5}=\frac{8}{5}\)
a) \(\frac{13}{19}+\frac{18}{19}+\frac{17}{19}\)
= \(\frac{31}{19}+\frac{17}{19}\)
= \(\frac{48}{19}.\)
b) \(\frac{3}{5}+\frac{3}{16}+\frac{13}{16}\)
= \(\frac{3}{5}+\left(\frac{3}{16}+\frac{13}{16}\right)\)
= \(\frac{3}{5}+\frac{16}{16}\)
= \(\frac{3}{5}+1\)
= \(\frac{3}{5}.\)
4/5 : 2/9 x 2/9 : 4/5
= 4/5 x 9/2 x 2/9 x 5/4
= ( 4/5 x 5/4 ) x ( 9/2 x 2/9 )
= 1x1
= 1
\(\frac{4}{5}:\frac{2}{9}\times\frac{2}{9}:\frac{4}{5}\)
\(=\frac{4}{5}\times\frac{9}{2}\times\frac{2}{9}\times\frac{5}{4}\)
\(=\left(\frac{4}{5}\times\frac{5}{4}\right)\times\left(\frac{2}{9}\times\frac{9}{2}\right)\)
\(=1\times1\)
\(=1\)
\(\frac{3}{4}:\frac{5}{6}+\frac{1}{4}:\frac{5}{6}\)
\(=\left(\frac{3}{4}+\frac{1}{4}\right):\frac{5}{6}\)
\(=1:\frac{5}{6}\)
\(=1\times\frac{6}{5}\)
\(=\frac{6}{5}\)
\(\frac{3}{4}:\frac{5}{6}+\frac{1}{4}:\frac{5}{6}\)
\(=\left(\frac{3}{4}+\frac{1}{4}\right):\frac{5}{6}\)
\(=1:\frac{5}{6}\)
\(=1\times\frac{6}{5}\)
\(=\frac{6}{5}\)
\(a,\frac{2}{5}+\frac{1}{6}+\frac{3}{5}\)
\(=\left(\frac{2}{5}+\frac{3}{5}\right)+\frac{1}{6}\)
\(=1+\frac{1}{6}\)
\(=\frac{7}{6}\)
Hok tốt!~
\(\frac{8}{15}:\frac{2}{11}+\frac{7}{15}:\frac{2}{11}\)
\(=\left(\frac{8}{15}+\frac{7}{15}\right):\frac{2}{11}\)
\(=1:\frac{2}{11}\)
\(=\frac{11}{2}\)
\(\frac{3}{4}.\frac{8}{9}.\frac{15}{16}.\frac{24}{25}.\frac{35}{36}\)
\(=\frac{3.2.4.3.5.4.6.5.7}{2.2.3.3.4.4.5.5.6.6}=\frac{7}{2.6}\)
\(=\frac{7}{12}\)
\(=\frac{1\cdot3\cdot2\cdot4\cdot3\cdot5\cdot4\cdot6\cdot5\cdot7}{2\cdot2\cdot3\cdot3\cdot4\cdot4\cdot5\cdot5\cdot6\cdot6}\)
\(=\frac{1\cdot7}{2\cdot6}\)
\(=\frac{7}{12}\)
a) 18/15 + 7/15+12/15 = 18/15 + 12/15 +7/15
= 30/15+ 7/15
= 37/15
b) 9/7+8/7 + 11/7 = 9/7 + 11/7 + 8/7
= 20/7 + 8/7
= 28/7
a) \(\frac{18}{15}+\frac{7}{15}+\frac{12}{15}=\frac{18}{15}+\frac{12}{15}+\frac{7}{15}=\frac{30}{15}+\frac{7}{15}\)\(=\frac{37}{15}\)
b)\(\frac{9}{7}+\frac{8}{7}+\frac{11}{7}=\frac{9}{7}+\frac{11}{7}+\frac{8}{7}=\)\(\frac{20}{7}+\frac{8}{7}=\frac{28}{7}\)
a)\(y=\frac{12x30}{15x36}\)=\(\frac{12x15x2}{15x12x3}\)=\(\frac{2}{3}\)
b) \(\frac{21x12}{54x42}\)=\(\frac{21x6x2}{6x9x21x2}\)=\(\frac{1}{9}\)
a) \(\frac{12x30}{15x36}=\frac{4x3x3x10}{5x3x3x12}=\frac{4x10}{5x12}=\frac{2x2x5x2}{5x2x6}=\frac{4}{6}=\frac{2}{3}\)
b) \(\frac{21x12}{54x42}=\frac{3x7x3x4}{18x3x7x6}=\frac{3x4}{18x6}=\frac{3x4}{3x6x6}=\frac{4}{24}=\frac{1}{6}\)