\(A=\frac{34}{7.13}+\frac{51}{13.22}+\frac{85}{22.37}+\frac{68}{37.49}\)

\(=\frac{17.2}{7.13}+\frac{17.3}{13.22}+\frac{17.5}{22.37}+\frac{17.4}{37.49}\)

\(=17\left(\frac{2}{7.13}+\frac{3}{13.22}+\frac{5}{22.37}+\frac{4}{37.49}\right)\)

\(=\frac{17}{3}\left(\frac{6}{7.13}+\frac{9}{13.22}+\frac{15}{22.37}+\frac{12}{37.49}\right)\)

\(=\frac{17}{3}\left(\frac{1}{7}-\frac{1}{13}+\frac{1}{13}-\frac{1}{22}+...+\frac{1}{37}-\frac{1}{49}\right)\)

\(=\frac{17}{3}\left(\frac{1}{7}-\frac{1}{49}\right)\)\(=\frac{17}{3}.\frac{6}{49}=\frac{17.2}{49}=\frac{34}{49}\)

Có : \(\frac{17}{24}=\frac{34}{48}\)

Vì 48 < 49 => \(\frac{34}{48}>\frac{34}{49}\). Hay \(\frac{17}{24}>A\)

cảm ơn Văn B ? nha !

5/7<7/6
17/13>45/52
4/3>99/100
34/56<42/53
97/252>85/163
73/97<91/95
 

5/7<7/6
17/13>45/52
4/3>99/100
34/56<42/53
97/252>85/163
73/97<91/95

ko có rảnh đâu nha con

a) \(\dfrac{12}{14}=\dfrac{1200}{1400}=\dfrac{1400-200}{1400}=1-\dfrac{200}{1400}\)

\(\dfrac{1212}{1414}=\dfrac{1414-200}{1414}=1-\dfrac{200}{1414}\)

vì \(\dfrac{200}{1414}< \dfrac{200}{1400}\)

Nên \(1-\dfrac{200}{1400}< 1-\dfrac{200}{1414}\)

Vậy \(\dfrac{12}{14}< \dfrac{1212}{1414}\)

Các bài sau tương tự

`#040911`

`a)`

\(37 \times 7 - 17 \times 11 + 13 \times 37 + 17 \times 21\)

`= 37 \times (7 + 13) + 17 \times (21 - 11)`

`= 37 \times 20 + 17 \times 10`

`= 10 \times (37 \times 2 + 17)`

`= 10 \times 91`

`= 910`

`b)`

\(5^5 \times 5^2 \div 5^4 - 2^8 \div 2^4\)

`=`\(5^{5+2-4}-2^{8-4}\)

`= 5^3 - 2^4`

`= 125 - 16`

`= 109`

`c)`

\(3^{11}\times12+3^{12}\times5-3^{14}\)

`=`\(3^{11}\times\left(12+3\times5-3^3\right)\)

`=`\(3^{11}\times\left(12+15-27\right)\)

`=`\(3^{11}\times0=0\)

a) = 259 - 187 + 481 + 357

= 910

b) = 5⁷ : 5⁴ - 2⁴

= 5³ - 2⁴ 

= 125 - 16

= 109

A = 1 + 3 + 5 + 7 +...+ 19

Dãy số trên là dãy số cách đều với khoảng cách là:  3 - 1 = 2

Số số hạng của dãy số trên là: ( 19 - 1): 2 + 1  = 10 

A = ( 19 + 1) \(\times\) 10 : 2 = 100

  52 - 42 + 37 + 28 - 38 + 63

= ( 52 + 28) - ( 42 + 38) + ( 37 + 63)

= 80 - 80 + 100

= 100 

 1 + 3 + 5 + 7 + 9+ 11 + 13 + 15 + 17 + 19

= (1+ 19) + (3 + 17) + (5 + 15) + (7 + 13) + (9 + 11)

= 20 + 20 + 20 + 20 + 20

= 100

 52 - 42 + 37 + 28 - 38 + 63

= (52 + 28) - ( 42 + 38) + (37 + 63)

= 80 - 80 + 100

= 100

Tick cho mình nhé!

tính = cách hợp lí nhất

g: \(=-457+237+23-123=-220-100=-320\)

h: \(=\left(1-3\right)+\left(5-7\right)+...+\left(41-43\right)+\left(45-47\right)\)

\(=\left(-2\right)+\left(-2\right)+...+\left(-2\right)+\left(-2\right)\)

\(=-2\cdot12=-24\)

i: \(=173+27-46-54-19=200-100-19=100-19=81\)

k: \(=-52+82+49-15+13-36\)

\(=30+34-23\)

=30+11

=41

l: \(=\left(3-5\right)+\left(7-9\right)+\left(11-13\right)+\left(15-17\right)\)

\(=\left(-2\right)+\left(-2\right)+\left(-2\right)+\left(-2\right)\)

=-8

m: \(=\left(1-2\right)+\left(3-4\right)+...+\left(2001-2002\right)+2003\)

\(=2003-1-1-...-1\)

\(=2003-1001=1002\)

n:Số số hạng là:

\(\left[\left(-51\right)-\left(-99\right)\right]:1+1=49\left(số\right)\)

Tổng là \(\left(-51-99\right)\cdot\dfrac{49}{2}=-3675\)

o: \(=-62-38+1523-2523-92\)

\(=-100+1000-92=900-92=808\)