28/....=21/24
121/143=..../13
DN
Những câu hỏi liên quan
Rút gọn các phân số sau: a) \(\dfrac{-21}{28}\); \(\dfrac{-39}{52}\); \(\dfrac{-24}{63}\); \(\dfrac{12}{-21}\) b, \(\dfrac{-270}{450}\); \(\dfrac{11}{-143}\); \(\dfrac{-132}{156}\); \(\dfrac{-26}{169}\)
bài 61
321-21.[(2.33+4 2 :32)-52]
160:{17+[32 .5(14+211:28)]}
22.52(20080 +8):32
2.33 +143:(20160.62-625:25)
a: =321-21*[(2*27+16:32)-52]
=321-21*[2+0,5]
=321-21*2,5=268,5
b: \(=\dfrac{160}{17+\left[9\cdot5\left(14+8\right)\right]}\)
\(=\dfrac{160}{17+45\cdot22}=\dfrac{160}{1007}\)
c: =100*9:3^2=100
d: =2*27+143:(36-25)
=54+143:11
=54+13=67
Đúng 1
Bình luận (0)
H24
24 tháng 2 2022 lúc 16:10
Tính theo mẫu :
Mẫu : 13/21 + 5/7 = 13/21 + 5 x 3 / 7 x 3 = 13/21 + 15/21 = 28/21
26/81 + 4/27
5/64 + 7/8
\(\dfrac{26}{81}+\dfrac{4}{27}=\dfrac{26+12}{81}=\dfrac{38}{81}\)
\(\dfrac{5}{64}+\dfrac{7}{8}=\dfrac{5+56}{64}=\dfrac{61}{64}\)
Đúng 3
Bình luận (0)
\(\dfrac{26}{81}+\dfrac{4}{27}=\dfrac{26}{81}+\dfrac{4\times3}{27\times3}=\dfrac{26}{81}+\dfrac{12}{81}=\dfrac{38}{81}\)
\(\dfrac{5}{64}+\dfrac{7}{8}=\dfrac{5}{64}+\dfrac{7\times8}{8\times8}=\dfrac{5}{64}+\dfrac{56}{64}=\dfrac{61}{64}\)
Đúng 3
Bình luận (0)
3/14 : 1/28 -13/21 :1/28 + 29/42 : 1/28 - 8 = ?
3/14:1/28-13/21:1/28+29/42:1/28-8=(3/14-13/21+29/42):1/28-8=2/7:1/28-8=8-8=0
Đúng 0
Bình luận (0)
c=3/14:1/28-13/21:1/28+29/42:1/28-8
13/28 - 3/21=??
Xem thêm câu trả lời
Bài 3. Thực hiện phép tính:
a, 21.( – 29) + (– 17).( – 13) c, (– 143):(– 13) – (– 5).(– 12)
b, (– 11)2.3 – [3 – (– 5)( – 4)] d, 17 – {(– 32) – (–3) 3 – [5.(– 41) – 12:(– 4)0 ]+ 1571}
GSRDFDXHGDSGHFDFG
Tính 5/11cua 451
Tính 5/11 của 451
\(C=\dfrac{3}{14}:\dfrac{1}{28}-\dfrac{13}{21}:\dfrac{1}{28}-\dfrac{29}{42}:\dfrac{1}{28}-8\)
\(=28\left(\dfrac{3}{14}-\dfrac{13}{21}-\dfrac{29}{42}\right)-8\\ =28\cdot\dfrac{-23}{21}-8=-\dfrac{92}{3}-8=-\dfrac{116}{3}\)
Đúng 2
Bình luận (0)
\(C=\dfrac{3}{14}:\dfrac{1}{28}-\dfrac{13}{21}:\dfrac{1}{28}-\dfrac{29}{42}:\dfrac{1}{28}-8\)
\(=28\left(\dfrac{3}{14}-\dfrac{13}{21}-\dfrac{29}{42}\right)-8\)
\(=28\left(\dfrac{9}{42}-\dfrac{26}{42}-\dfrac{29}{42}\right)-8\)
\(=28\cdot\dfrac{-46}{42}-8\)
\(=\dfrac{-116}{3}\)
Đúng 0
Bình luận (0)
Tinh tong:
13/3+13/6+13/10+13/15+13/21+13/28+13/36+13/45+13/55
Đặt \(A=\frac{13}{3}+\frac{13}{6}+\frac{13}{10}+\frac{13}{15}+\frac{13}{21}+\frac{13}{28}+\frac{13}{36}+\frac{13}{45}+\frac{13}{55}\)
\(A=\frac{26}{6}+\frac{26}{12}+\frac{26}{20}+\frac{26}{30}+\frac{26}{42}+\frac{26}{56}+\frac{26}{72}+\frac{26}{90}+\frac{26}{110}\)
\(A=26\left(\frac{1}{6}+\frac{1}{12}+\frac{1}{20}+\frac{1}{30}+\frac{1}{42}+\frac{1}{56}+\frac{1}{72}+\frac{1}{90}+\frac{1}{110}\right)\)
\(A=26\left(\frac{1}{2.3}+\frac{1}{3.4}+\frac{1}{4.5}+\frac{1}{5.6}+\frac{1}{6.7}+\frac{1}{7.8}+\frac{1}{8.9}+\frac{1}{9.10}+\frac{1}{10.11}\right)\)
\(A=26\left(\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+\frac{1}{4}-\frac{1}{5}+...+\frac{1}{10}-\frac{1}{11}\right)\)
\(A=26\left(\frac{1}{2}-\frac{1}{11}\right)\)
\(A=26.\frac{9}{22}\)
\(A=\frac{117}{11}\)
Vậy \(A=\frac{117}{11}\)
Chúc bạn học tốt ~
Đúng 0
Bình luận (0)
\(\text{c) \dfrac{3}{14} : \dfrac{1}{28} - \dfrac{13}{21} : \dfrac{1}{28} - \dfrac{29}{42} : \dfrac{1}{28} - 8}\)
c: \(\dfrac{3}{14}:\dfrac{1}{28}-\dfrac{13}{21}:\dfrac{1}{28}\)
\(=28\left(\dfrac{3}{14}-\dfrac{13}{21}\right)\)
\(=28\cdot\left(\dfrac{9}{42}-\dfrac{26}{42}\right)\)
\(=28\cdot\dfrac{-17}{42}=\dfrac{-34}{3}\)
Đúng 0
Bình luận (0)