Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
`1/3 + 5/4`
`= 4/12 + 15/12`
`= 19/12
__
`4/12 - 1/15`
`= 1/3 -1/15`
`= 5/15 -1/15`
`=4/15`
__
`2/3 xx 15/8`
`= (2xx15)/(3xx88)`
`= 30/24`
`=5/4`
__
`2/3 : 8/21`
`= 2/3 xx 21/8`
`= (2xx21)/(3xx8)`
`= 42/24`
`=7/4`
1/3+5/4=4/12+15/12
=19/12
4/12-1/15=20/60-4/60
=16/60=4/15
2/3x15/8=30/24=5/4
2/3:8/21=42/24=7/4
nhớ cho a tích nhé =)) a bị bịp nhiều rồi
a) (27 -18) : 3 =?
Cách 1: (27 -18) : 3
= 9 : 3 = 3
Cách 2:(27 -18) : 3
= 27 : 3 - 18 : 3
= 9 - 6 = 3
b) (64 - 32) : 8 = ?
Cách 1:(64 - 32) : 8
= 32 : 8 = 4
Cách 2:(64 - 32) : 8
= 64 : 8 - 32 : 8
= 8 - 4 = 4
Nói thêm: Khi chia một hiệu cho một số, ta có thể chia số bị trừ và số trừ cho số đó (nếu chia hết), rồi trừ hai kết quả cho nhau.
(27 -18) : 3
= 27 : 3 - 18 : 3
a)2/3x4/7=8/21
b)8/21:2/3=8/21x3/2=24/42=4/7
c)8/21:4/7=8/21x7/4=56/85=7//12
d)4/7X2/3=8/21
\(\frac{13}{21}+3+\frac{29}{21}\)
\(=\frac{42}{21}+3\)
\(=2+3\)
\(=5\)
\(\frac{3}{4}+\frac{3}{5}+\frac{2}{8}+\frac{4}{10}\)
\(=\frac{3}{4}+\frac{3}{5}+\frac{1}{4}+\frac{2}{5}\)
\(=1+1\)
\(=2\)
\(a,\dfrac{4}{5}+\dfrac{2}{7}=\dfrac{28}{35}+\dfrac{10}{35}=\dfrac{38}{35}.\)
\(b,2-\dfrac{8}{9}=\dfrac{18}{9}-\dfrac{8}{9}=\dfrac{10}{9}.\)
\(c,\dfrac{5}{8}\times3=\dfrac{5\times3}{8}=\dfrac{15}{8}.\)
\(d,5:\dfrac{6}{21}=5\times\dfrac{21}{6}=\dfrac{5\times21}{6}=\dfrac{105}{6}=\dfrac{35}{2}.\)
\(đ,\dfrac{3}{5}\times\dfrac{4}{5}\times\dfrac{6}{7}=\dfrac{3\times4\times6}{5\times5\times7}=\dfrac{72}{175}.\)
\(a,\dfrac{4}{5}+\dfrac{2}{7}=\dfrac{28}{35}+\dfrac{10}{35}=\dfrac{38}{35}\)
\(b,2-\dfrac{8}{9}=\dfrac{18}{9}-\dfrac{8}{9}=\dfrac{10}{9}\)
\(c,\dfrac{5}{8}\times3=\dfrac{5\times3}{8\times1}=\dfrac{15}{8}\)
\(d,\dfrac{3}{5}\times\dfrac{4}{5}\times\dfrac{6}{7}=\dfrac{3\times4\times6}{5\times5\times7}=\dfrac{72}{175}\)
11/15 + 8/5= Tính phân số
6/7 - 5/21=
25/4 x 16/100
7 x 2/49 =
4/3 : 2/9
5/8 : 25 =
\(\dfrac{26}{81}+\dfrac{4}{27}=\dfrac{26+12}{81}=\dfrac{38}{81}\)
\(\dfrac{5}{64}+\dfrac{7}{8}=\dfrac{5+56}{64}=\dfrac{61}{64}\)
\(\dfrac{26}{81}+\dfrac{4}{27}=\dfrac{26}{81}+\dfrac{4\times3}{27\times3}=\dfrac{26}{81}+\dfrac{12}{81}=\dfrac{38}{81}\)
\(\dfrac{5}{64}+\dfrac{7}{8}=\dfrac{5}{64}+\dfrac{7\times8}{8\times8}=\dfrac{5}{64}+\dfrac{56}{64}=\dfrac{61}{64}\)
7/8:2=7/8*1/2=7/16
9/11:3=9/11*1/3=9/33=3/11
6:3/7=6/1*7/3=42/3=14
14:21/5=14/1*5/21==70/21
\(\frac{7}{8}:2=\frac{7}{8}.\frac{1}{2}=\frac{7}{16}\)
\(\frac{9}{11}:3=\frac{9}{11}.\frac{1}{3}=\frac{9}{33}=\frac{3}{11}\)
\(6:\frac{3}{7}=6.\frac{7}{3}=14\)
\(14:\frac{21}{5}=14.\frac{5}{21}=\frac{70}{21}\)
****
