\(A=\dfrac{34}{11}.\dfrac{27}{46}.\dfrac{23}{17}.\dfrac{22}{9}\)

\(A=\dfrac{34.27.23.22}{11.46.17.9}=\dfrac{17.2.9.3.23.11.2}{11.23.2.17.9}=\dfrac{2.3}{1}=\dfrac{6}{1}=6\)

???????

* là gì vậy bạn

Tính từ từ là ra nhé. Kết quả = 282

nghi phét tính ra luôn

\(\frac{34}{11}\cdot\frac{1269}{46}\cdot\frac{23}{17}\cdot\frac{22}{9}\)

\(=\frac{34\cdot1269\cdot23\cdot22}{11\cdot46\cdot17\cdot9}\)

\(=\frac{17\cdot2\cdot141\cdot9\cdot23\cdot11\cdot2}{11\cdot23\cdot2\cdot17\cdot9}\)

\(=\frac{2\cdot141\cdot2}{2}\)

\(=141\cdot2\)

\(=282\)

\(34/11×1269/46×23/17×22/9=282\)

34/11 * 1269/46 * 23/17 * 22/9

=(34 x 1269 x 23 x 22) / (11 x 46 x 17 x 9)

=(17 x 2 x 141 x 9 x 23 x 11 x 2) / (11 x 23 x 2 x 17 x 9)

=(141 x 2) / 1

=282/1

=282

                                                                                @_@CHÚC BẠN HỌC TỐT!!!@_@

BAI 1 ; 

Bài 2: 

a, \(\dfrac{5}{23}\) \(\times\) \(\dfrac{17}{26}\) + \(\dfrac{5}{23}\) \(\times\) \(\dfrac{9}{26}\) 

= \(\dfrac{5}{23}\) \(\times\) ( \(\dfrac{17}{26}\) + \(\dfrac{9}{26}\))

= \(\dfrac{5}{23}\) \(\times\) \(\dfrac{26}{26}\)

= \(\dfrac{5}{23}\) 

b, \(\dfrac{3}{4}\) \(\times\) \(\dfrac{7}{9}\) + \(\dfrac{7}{4}\)  \(\times\) \(\dfrac{3}{9}\)

= \(\dfrac{7}{12}\) + \(\dfrac{7}{12}\)

= \(\dfrac{14}{12}\)

= \(\dfrac{7}{6}\)

1,a) \(\dfrac{17}{20}=\dfrac{51}{60};\dfrac{13}{15}=\dfrac{52}{60}\)

1

a)\(\frac{27}{5}\text{x}\frac{91}{12}\text{x}\frac{125}{9}\text{x}\frac{96}{13}=\frac{27}{9}\text{x}\frac{91}{13}\text{x}\frac{125}{5}\text{x}\frac{96}{12}=3\text{x}7\text{x}25\text{x}8\)

Đến đây tự tính nha !

b)\(\frac{2539}{35}\text{x}\frac{7}{90}+\frac{561}{35}\text{x}\frac{7}{90}=\frac{7}{90}\text{x}\left(\frac{2539}{35}+\frac{561}{35}\right)=\frac{7}{90}\text{x}\frac{3100}{35}=\frac{3100}{90}\text{x}\frac{7}{35}=\frac{310}{9}\text{x}\frac{1}{5}=\frac{62}{9}\)

1. 27/5 x 91/12 x 125/9 x 96/13

2. 2539/35 x 7/90 + 561/35 x 7/90

3. 31/7 : (2/5 x 31/7)

4. (29 x 15/23 x 36/29) : 5/23

3)\(\dfrac{31}{7}\) : (\(\dfrac{2}{5}\times\dfrac{31}{7}\) )

=\(\dfrac{31}{7}\) : \(\dfrac{2}{5}\times\dfrac{31}{7}\)

= \(\dfrac{31}{7}:\dfrac{31}{7}\times\dfrac{2}{5}\)

= \(\dfrac{2}{5}\)

4) (\(29\times\dfrac{15}{23}\times\dfrac{31}{7}\)) : \(\dfrac{5}{23}\) 

=\(29\times\dfrac{15}{23}\times\dfrac{31}{7}:\dfrac{5}{23}\)

= \(29\times\dfrac{31}{7}\times\dfrac{15}{23}:\dfrac{5}{23}\)

= 29 x \(\dfrac{31}{7}\times\dfrac{15}{23}\times\dfrac{23}{5}\)

= 29 x \(\dfrac{31}{7}\times3\)

= 29 x 3 x \(\dfrac{31}{7}\) 

= 87 x \(\dfrac{31}{7}\) 

= \(\dfrac{2697}{7}\)

áp dụng kiến thức tính nhanh ý

1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39+40+41+42+43+44+45+46+47+48+49+50=1275

= 1275

=1275

=1245

Có ai rảnh đâu mà đi ngồi cộng ngần đấy số ra.