Ai biết trả lời nhanh giúp mình nha mình đang cần luôn rất rất rất rất gấp.

mk chịu

Ai biết trả lời nhanh giúp mình mình kết bạn cùng

sorry bn nha bài này chịu 

a)    \(\frac{3}{16}+\frac{4}{15}+\frac{5}{16}+\frac{1}{15}\)

\(=\left(\frac{3}{16}+\frac{5}{16}\right)+\left(\frac{4}{15}+\frac{1}{15}\right)\)

\(=\frac{1}{2}+\frac{1}{3}\)

\(=\frac{5}{6}\)

b)   \(\frac{6}{7}\times\frac{8}{15}\times\frac{7}{6}\times\frac{15}{16}\)

\(=\left(\frac{6}{7}\times\frac{7}{6}\right)\times\left(\frac{8}{15}\times\frac{15}{16}\right)\)

\(=1\times\frac{1}{2}=\frac{1}{2}\)

c)   \(\frac{19}{20}\times\frac{13}{21}+\frac{9}{20}\times\frac{8}{21}\)

\(=\frac{19\times13}{20\times21}+\frac{9\times8}{20\times21}\)

\(=\frac{247}{420}+\frac{72}{420}\)

\(=\frac{319}{420}\)

còn phần D đâu bn 

a,\(\frac{4}{3}\)x \(\frac{9}{8}\)x \(\frac{16}{15}\)x \(\frac{25}{24}\)

= \(\frac{5}{3}\)

b, \(\frac{4}{3}\)x \(\frac{9}{8}\)x \(\frac{16}{15}\)x \(\frac{25}{24}\)x \(\frac{36}{35}\)x \(\frac{49}{48}\)x \(\frac{64}{63}\)x \(\frac{81}{80}\)

= \(\frac{9}{5}\)

chi tiết hơn đc k bn

sao chưa ai giúp mình vậy

a. \(495:\left(3\times5\times11\right)\)

\(=\left(3\times3\times5\times11\right):\left(3\times5\times11\right)\)

\(=3\times3\times5\times11:3:5:11\)

\(=\left(3:3\right)\times\left(5:5\right)\times\left(11:11\right)\times3\)

\(=1\times1\times1\times3=3\)

b. \(\left(15\times18\times24\right):\left(5\times9\times12\right)\)

\(=15\times18\times24:5:9:12\)

\(=\left(15:5\right)\times\left(18:9\right)\times\left(24:12\right)\)

\(=3\times2\times2\)

\(=12\)

c. \(\left(27+45+18+81\right):9\)

\(=\left(27:9\right)+\left(45:9\right)+\left(18:9\right)+\left(81:9\right)\)

\(=3+5+2+9\)

\(=19\)

a 495 : (3 x 5 x 11)

=495 : 165

= 3 

b (15 x 18 x 24) : (5 x 9 x 12)

= (270 x 24) : (45 x 12)

= 6480 :  540

12

c (27 + 45 + 18 + 81) : 9

=171 : 9 

=19

a:Sửa đề: 1x3+2x4+...+99x101

\(=1\times\left(1+2\right)+2\times\left(2+2\right)+\cdots+99\times\left(99+2\right)\)

\(=\left(1\times1+2\times2+\cdots+99\times99\right)+2\times\left(1+2+\cdots+99\right)\)

\(=\frac{99\times\left(99+1\right)\times\left(2\times99+1\right)}{6}+2\times\frac{99\times100}{2}\)

\(=\frac{99\times100\times199}{6}+99\times100=33\times50\times199+99\times100\)

\(=33\times50\times\left(199+3\times2\right)=33\times50\times205=338250\)

b: \(\frac89\times\frac{15}{16}\times\ldots\times\frac{2499}{2500}\)

\(=\left(1-\frac19\right)\times\left(1-\frac{1}{16}\right)\times\ldots\times\left(1-\frac{1}{2500}\right)\)

\(=\left(1-\frac13\right)\times\left(1-\frac14\right)\times\ldots\times\left(1-\frac{1}{50}\right)\times\left(1+\frac13\right)\times\left(1+\frac14\right)\times\ldots\times\left(1+\frac{1}{50}\right)\)

\(=\frac23\times\frac34\times\ldots\times\frac{49}{50}\times\frac43\times\frac54\times\ldots\times\frac{51}{50}=\frac{2}{50}\times\frac{51}{3}=\frac{17}{25}\)