![](https://rs.olm.vn/images/avt/0.png?1311)
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
a)
\(\frac{1.2+2.4+3.6+4.8+5.10}{3.4+6.8+9.12+12.16+15.20}\)
\(\frac{2.3\left(1.2\right)+2.3\left(2.4\right)+2.3\left(3.6\right)+2.3\left(4.8\right)+2.3\left(5.10\right)}{3.4\left(3.4+6.8+9.12+12.16+15.20\right)}\)
\(=\frac{\left(3.4+6.8+9.12+12.16+15.20\right)}{2.3\left(3.4+6.8+9.12+12.16+15.20\right)}=\frac{1}{2.3}=\frac{1}{6}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(\dfrac{15}{16}:\dfrac{5}{8}\times\dfrac{3}{4}\)
\(=\dfrac{15}{16}\times\dfrac{8}{5}\times\dfrac{3}{4}\)
\(=\dfrac{3}{2}\times\dfrac{3}{4}\)
\(=\dfrac{9}{8}\)
_________________
\(\dfrac{21}{4}\times\dfrac{16}{14}\times\dfrac{1}{2}\times\dfrac{8}{3}\)
\(=6\times\dfrac{4}{3}\)
\(=8\)
![](https://rs.olm.vn/images/avt/0.png?1311)
a) \(2+\dfrac{3}{4}\)
\(=\dfrac{8}{4}+\dfrac{3}{4}\)
\(=\dfrac{8+3}{4}\)
\(=\dfrac{11}{4}\)
b) \(\dfrac{1}{3}+\dfrac{3}{2}-\dfrac{7}{4}\)
\(=\dfrac{4}{12}+\dfrac{18}{12}-\dfrac{21}{12}\)
\(=\dfrac{4+18-21}{12}\)
\(=\dfrac{1}{12}\)
c) \(\dfrac{1}{6}+\dfrac{3}{8}-\dfrac{1}{4}\)
\(=\dfrac{4}{24}+\dfrac{9}{24}-\dfrac{6}{24}\)
\(=\dfrac{4+9-6}{24}\)
\(=\dfrac{7}{24}\)
d) \(\dfrac{5}{12}+\dfrac{3}{8}\times\dfrac{4}{9}\)
\(=\dfrac{5}{12}+\dfrac{3\times4}{8\times9}\)
\(=\dfrac{5}{12}+\dfrac{1}{6}\)
\(=\dfrac{5}{12}+\dfrac{2}{12}\)
\(=\dfrac{7}{12}\)
e) \(\dfrac{4}{5}-\dfrac{1}{5}\times\dfrac{7}{2}\)
\(=\dfrac{4}{5}-\dfrac{1\times7}{5\times2}\)
\(=\dfrac{4}{5}-\dfrac{7}{10}\)
\(=\dfrac{8}{10}-\dfrac{7}{10}\)
\(=\dfrac{8-7}{10}\)
\(=\dfrac{1}{10}\)
f) \(\dfrac{16}{9}-\dfrac{4}{15}:\dfrac{2}{5}\)
\(=\dfrac{16}{9}-\dfrac{4}{15}\times\dfrac{5}{2}\)
\(=\dfrac{16}{9}-\dfrac{4\times5}{15\times2}\)
\(=\dfrac{16}{9}-\dfrac{2}{3}\)
\(=\dfrac{16}{9}-\dfrac{6}{9}\)
\(=\dfrac{16-6}{9}\)
\(=\dfrac{10}{9}\)
a: =8/4+3/4=11/4
b: =4/12+18/12-21/12=1/12
c: =4/24+9/24-6/24=7/24
d: =5/12+12/72
=5/12+1/6
=5/12+2/12=7/12
e: =4/5-7/10
=8/10-7/10=1/10
f: =16/9-4/15*5/2
=16/9-20/30
=16/9-2/3
=16/9-6/9=10/9
![](https://rs.olm.vn/images/avt/0.png?1311)
a; \(\dfrac{1}{4}\) + \(\dfrac{2}{5}\) + \(\dfrac{6}{8}\) + \(\dfrac{9}{15}\) + \(\dfrac{8}{1}\)
= (\(\dfrac{1}{4}\) + \(\dfrac{6}{8}\)) + (\(\dfrac{2}{5}\) + \(\dfrac{9}{15}\)) + \(\dfrac{8}{1}\)
= (\(\dfrac{1}{4}\) + \(\dfrac{3}{4}\)) + (\(\dfrac{2}{5}\) + \(\dfrac{3}{5}\)) + 8
= 1 + 1 + 8
= 2 + 8
= 10
b; \(\dfrac{1}{2}\) + \(\dfrac{2}{4}\) + \(\dfrac{3}{6}\) + \(\dfrac{4}{8}\) + \(\dfrac{5}{10}\) + \(\dfrac{6}{12}\) + \(\dfrac{7}{14}\) + \(\dfrac{8}{16}\) + \(\dfrac{10}{20}\)
= \(\dfrac{1}{2}\) + \(\dfrac{1}{2}\) x (\(\dfrac{2}{2}\) + \(\dfrac{3}{3}\) + \(\dfrac{4}{4}\) + \(\dfrac{5}{5}\)+ \(\dfrac{6}{6}+\dfrac{7}{7}+\dfrac{8}{8}\) + \(\dfrac{10}{10}\))
= \(\dfrac{1}{2}\) + \(\dfrac{1}{2}\) x (1 + 1 +1 + 1+ 1+ 1+ 1 +1)
= \(\dfrac{1}{2}\) + \(\dfrac{1}{2}\) x 1 x 8
= \(\dfrac{1}{2}\) + \(\)\(\dfrac{1}{2}\) x 8
= \(\dfrac{1}{2}\) + 4
= \(\dfrac{9}{2}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
a) 2/8+5/15+9/12+4/6
=1/4+1/3+3/4+2/3
=(1/4+3/4)+(1/3+2/3)
=1 + 1
=2
b) 1/2+1/4+1/8+1/16
=8/16+4/16+2/16+1/16
=15
c) 1/3-1/4+2/3
=4/12-3/12+8/12
=3/4
d) 1/2-1/3+1/4-1/6
=(1/2-1/4) + (1/3-1/6)
=(2/4-1/4)+(2/6-1/6)
=1/4+1/6
=6/24+4/24
=5/12
k cho mình nha
![](https://rs.olm.vn/images/avt/0.png?1311)
a.1/4 +3/8 +5/16=15/16
b, 3/5 - 1/3 -1/6=1/10
c, 4/7 *5/8 *7/12=5/24
d. 25/28 : 15/24 * 6/7=60/49
![](https://rs.olm.vn/images/avt/0.png?1311)
1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10=55
2 + 4 + 6 + 8 + 10 + 12 + 14 + 16 + 18 + 20=110
1 + 3 + 5 + 7 + 9 + 11 + 13 + 15 + 17 + 19=100
k mk nha pạn hiền!
10 +1 = 11 có 10 số vậy thì 10 : 2 = 5 thì sẽ bằng 5x11 = 55
2 + 20 = 22 cũng có 10 số lấy 10 : 2 = 5 se bang 22 x5 = 110
1+19 = 20 , 10 : 2 = 5 , 20x5 = 100
![](https://rs.olm.vn/images/avt/0.png?1311)
1+1+2+2+3+3+4+4+5+5+6+6+7+7+8+9+8+9+10+12+13+14+15+16+17+18+19+20+30+1000000=10000274
4\(\frac{1}{4}\)+\(\frac{15}{16}\):\(\frac{3}{8}\)
=\(\frac{17}{4}\)+\(\frac{15}{16}\)x\(\frac{8}{3}\)
=\(\frac{17}{4}\)+\(\frac{5}{2}\)
=\(\frac{17}{4}\)+\(\frac{10}{4}\)
\(\frac{27}{4}\)
Hok tốt!
=17/4+15/16*8/3
17/4+5/2
17/4+10,4
27/4
HT nha k mình với