19/11 + [ 8/13 + 3,11 ]

= [ 19/11 + 3/11 ] + 8/13

=   22/11 + 8/13

= 2 + 8/13

= 34/13

19/11 + ( 8/13 + 3/11 ) = 19/11 + 8/13 + 3/11 = ( 19/11 + 3/11 ) + 8/13 = 2 + 8/13 = 26/13 + 8/13 = 34/13

k mk nha mk k lai

\(2\frac{8}{13}\)

19/11 + [8/13 + 3/11]

=19/11+ 3/11+ 8/13

= 2 + 8/13

= 34/13

=\(\frac{19}{11}+\frac{3}{11}+\frac{8}{13}\)

=\(2+\frac{8}{13}\)

=\(2\frac{8}{13}\)

19/11+(8/13+3/11)=(19/11+3/11)+8/13=2+8/13=26/13+8/13=34/13

=54 x 9 x(2 x 5 )

=54 x 9 x 10 

= 486 x 10

= 4860

54.2.9.5

=(54.9).(2.5)

=486.10

=4860

. có nghĩa là nhân

54 x 2 x 9 x 5 

= 54 x 9 x 2 x 5

= 54 x 9 x 10

= 486 x 10

2x25x50xx8=(25x8)x(50x2)=200x100=20000

12x11+21x11+11x33=11x(12+21+33)=11x66=726

2*25*50*8

=(2*50)*(25*8)

=100*200=20000

12*11+21*11+11*33

=11*(12+21+33)

=11*66=676

2 x 25 x 50 x 8  = (8 x 25) x (50 x 2) = 200 x 100 = 20000

b) 12 x 11 + 21 x 11 + 11 x 13 = 11 x (12 + 21 + 33) 

= 11 x 66 = 726

3/2 + 4/9 + 4/7 + 5/9 = 43/14

=3x2/3 x 2/4

=2x1/2

=1

=1

k cko mik nha mái pn

=(2²)¹⁹+(2³)7/(2⁸)⁴+(2⁵)³

=2³⁸+2²¹/2²³+2¹⁵

=2²¹(2¹⁷+1)/2¹⁵(2¹⁷+1)

=2⁶

nếu dung tích cho mình nhé

bằng 45 nha

1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9

= (1 + 9) + (2 + 8) + (3 + 7) + (4 + 6) +5

= 10 + 10 + 10 +10 + 5

= 10 x 4 + 5

= 40 + 5

= 45

1+2+3+4+5+6+7+8+9

=[1+9]+[2+8]+[3+7]+[4+6]+5

=10+10+10+10+5

=40+5

=45