Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
\(a,\frac{2}{5}+\frac{3}{4}=\frac{8}{20}+\frac{15}{20}=\frac{23}{20}\)
\(\frac{5}{8}+\frac{7}{2}=\frac{5}{8}+\frac{28}{8}=\frac{33}{8}\)
\(\frac{4}{9}+\frac{5}{18}=\frac{8}{18}+\frac{5}{18}=\frac{13}{18}\)
\(\frac{5}{8}+\frac{9}{16}=\frac{10}{16}+\frac{9}{16}=\frac{19}{16}\)
\(b,\frac{9}{5}-\frac{5}{9}=\frac{81}{45}-\frac{25}{45}=\frac{56}{45}\)
\(\frac{12}{7}-\frac{17}{2}=\frac{24}{14}-\frac{119}{14}=-\frac{95}{14}\)
\(\frac{11}{8}-\frac{8}{11}=\frac{121}{88}-\frac{64}{88}=\frac{57}{88}\)
\(\frac{17}{6}-\frac{6}{17}=\frac{289}{102}-\frac{36}{102}=\frac{253}{102}\)
Số số hạng của dãy số là:
(17-1) :1 + 1 = 17 (số hạng)
Tổng của dãy số là:
(1+17) x 17 : 2 = 153
Đáp số: 153
\(\dfrac{11}{12}x\dfrac{6}{9}-\dfrac{3}{8}=\dfrac{66}{108}-\dfrac{3}{8}=\dfrac{17}{72}\)
\(\dfrac{5}{7}:\dfrac{9}{14}-\dfrac{17}{18}=\dfrac{70}{63}-\dfrac{17}{18}=\dfrac{1}{6}\)
\(\dfrac{11}{12}\) x \(\dfrac{6}{9}-\dfrac{3}{8}=\dfrac{11}{18}-\dfrac{3}{8}=\dfrac{88}{144}-\dfrac{54}{144}=\dfrac{34}{144}=\dfrac{17}{72}\)
\(\dfrac{5}{7}:\dfrac{9}{14}-\dfrac{17}{18}\)\(=\dfrac{5}{7}\) x \(\dfrac{14}{9}-\dfrac{17}{18}=\dfrac{10}{9}-\dfrac{17}{18}=\dfrac{20}{18}-\dfrac{17}{18}=\dfrac{3}{18}=\dfrac{1}{6}\)
a, (6/11+5/11)x3/17
c1:=1x3/17
=3/17
c2:=6/11x3/17+5/11x3/17
=18/197+15/187
=33/187
=3/17
b,3/5x7/9-3/5x2/9
c1:=21/45-6/45
=15/45
=1/3
c2:=3/5x(7/9-2/9)
=3/5x5/9
=1/3
c,( 6/7-4/7):2/5
c1:=2/7:2/5
=2/7x5/2
=5/7
c2,6/7:2/5-4/7:2/5
=6/7x5/2-4/7x5/2
=15/7-10/7
=5/7
d,8/15:2/11+7/15:2/11
c1:=(8/15+7/15):2/11
=1x11/2
=11/2
c2:=8/15x11/2+7/15x11/2
=88/30+77/30
=165/30
=11/2
a) (\(\frac{6}{11}\) + \(\frac{5}{11}\)) x \(\frac{3}{17}\)= \(\frac{11}{11}\) x \(\frac{3}{17}\)= \(1\) x\(\frac{3}{17}\)= \(\frac{3}{17}\)
b) \(\frac{3}{5}\)x\(\frac{7}{9}\)- \(\frac{3}{5}\)x \(\frac{2}{9}\) = \(\frac{3}{5}\)x (\(\frac{7}{9}\)- \(\frac{2}{9}\))= \(\frac{3}{5}\) x \(\frac{5}{9}\)= \(\frac{3}{9}\)
c) (\(\frac{6}{7}\)- \(\frac{4}{7}\)) : \(\frac{2}{5}\)= \(\frac{2}{7}\) x \(\frac{5}{2}\)= \(\frac{5}{7}\)
d) \(\frac{8}{15}\) : \(\frac{2}{11}\) + \(\frac{7}{15}\): \(\frac{2}{11}\)= ( \(\frac{8}{15}\)+ \(\frac{7}{15}\)) x \(\frac{11}{2}\)= 1 x \(\frac{11}{2}\)= \(\frac{11}{2}\)
Chúc học tốt nha!
\(\dfrac{1}{2}-\dfrac{3}{8}=\dfrac{4}{2\times4}-\dfrac{3}{8}=\dfrac{4}{8}-\dfrac{3}{8}=\dfrac{1}{8}\)
\(\dfrac{4}{3}-\dfrac{8}{15}=\dfrac{4\times5}{3\times5}-\dfrac{8}{15}=\dfrac{20}{15}-\dfrac{8}{15}=\dfrac{12}{15}=\dfrac{4}{5}\)
\(\dfrac{5}{6}-\dfrac{7}{12}=\dfrac{5\times2}{6\times2}-\dfrac{7}{12}=\dfrac{10}{12}-\dfrac{7}{12}=\dfrac{3}{12}=\dfrac{1}{4}\)
\(\dfrac{11}{4}-\dfrac{9}{8}=\dfrac{11\times2}{4\times2}-\dfrac{9}{8}=\dfrac{22}{8}-\dfrac{9}{8}=\dfrac{13}{8}\)
\(\dfrac{17}{16}-\dfrac{3}{4}=\dfrac{17}{16}-\dfrac{3\times4}{4\times4}=\dfrac{17}{16}-\dfrac{12}{16}=\dfrac{5}{16}\)
\(\dfrac{31}{36}-\dfrac{5}{6}=\dfrac{31}{36}-\dfrac{5\times6}{6\times6}=\dfrac{31}{36}-\dfrac{30}{36}=\dfrac{1}{36}\)
\(\dfrac{11}{12}\times\dfrac{6}{9}-\dfrac{3}{8}=\dfrac{11}{18}-\dfrac{3}{8}=\dfrac{17}{72}\)
\(\dfrac{5}{7}:\dfrac{9}{14}-\dfrac{17}{18}=\dfrac{10}{9}-\dfrac{17}{18}=\dfrac{3}{18}=\dfrac{1}{6}\)
11/12 x 6/9 - 3/8
= 11/18 - 3/8
= 17/72
5/7 : 9/14 - 17/18
= 10/9 - 17/18
= 1/6
17/5 - 4/9 + 8/9
= 17/5 + 4/9
= 173/45
\(\dfrac{17}{5}\) - \(\dfrac{4}{9}\) + \(\dfrac{8}{9}\)
= \(\dfrac{17}{5}\) + (\(\dfrac{8}{9}\) - \(\dfrac{4}{9}\))
= \(\dfrac{17}{5}\) + \(\dfrac{4}{9}\)
= \(\dfrac{153}{45}\) + \(\dfrac{20}{45}\)
= \(\dfrac{173}{45}\)