=5400

\(\text{6.75.1.25-0.675.120-6.75.13}\)

\(=5400\)

Bạn nhé !!! k với nha !!!

=5400

a. 20,13 x 84,5 x 20,13

= 20,13 x 84,5 x 20,13 x 1

= 20,13 x ( 84,5 + 1 )

= 20,13 x 85,55

b. 4,5 x 11/5 + 5,5 x 11/5

= ( 4,5 + 5,5 ) x 11/5

= 10 x 11/5

= 22

a]20,13 * 84,5 * 20,13 = 20,13 * 2 * 84,5

                                 = 20,13 * 169

                                 = 3401,97

b] 4,5 * 11/5 + 5,5 * 11/5 = 11/5 * [4,5 + 5,5]

                                        = 2,2 * 10

                                        = 22

Giải thích hơi dài, tớ chỉ ghi đ/s thôi.

Đ/s: 1.

20/11*33/23*69/180=20*33*69/11*23*180=9/9=1

a/ = 7,8 x ( 34,5 + 15,5 ) = ..... tự tính 

b/ 11/5 x (3/7 +4/7 )= .......tự tính 

mk nhé

a, 7,8 x 34,5 +15,5 x 7,8 = 7,8 x ( 34,5 + 15,5) =7,8 x 50 =390

b, 3/7 x 11/5 +4/7 x 11/5 = 11/5 x ( 3/7 +4/7) = 11/5 x1=11/5 

=.= hok tốt!!

7,8 .  (34,5 + 15,5 ) 

= 7,8 .50.0

=39,000

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

a) 3/5x7/9+11/9x3/5

=3/5 x(7/9+11/9)

= 3/5x2

=6/5

b)14/13:1/2+3/13x2-2x7/13

= 14/13 x 2 +3/13 x2 - 2x7/13

=2 x (14/13 +3/13 -7/13)

= 2 x 10/13

= 20/13

a) 3/5 x 7/9 + 11/9 x 3/5 - 3/10

=  3/5 x 7/9 + 11/9 x 3/5 - 3/5 x 2

=  3/5 x ( 7/9 + 11/9 - 2 )

=  3/5 x 0

=  0

b) 14/13 : 1/2 + 3/13 x 2 - 2 x 7/13

=  14/13 x 2/1 + 3/13 x 2 - 2 x 7/13

=  ( 14/13 + 3/13 - 7/13 ) x 2

=  10/13 x 2 = 20/13

chẳng hiể gì cả

\(\frac{20}{11}X\)\(\frac{33}{23}X\)\(\frac{69}{180}\)\(=\frac{20X11X3X23X3}{11X23X20X3X3}=\)\(1\)

TỚI CHỖ \(\frac{20X11X3X23X3}{11X23X20X3X3}\)THÌ BẠN GẠCH CHÉO NHỮNG SỐ GIỐNG NHAU NHA

20/11 x 33/23 x 23/60 = 20x33x23/11x23x60 = 1x3x1/1x1x3 = 3/3 = 1

a)\(\frac{20}{11}.\frac{33}{23}.\frac{69}{180}=\frac{9}{9}=1\)

b: (675,98 + 888,66 + 111,34) x 0,01

= (675,98 + [888,66 + 111,34]) x 0,01

= (675,98 + 1000) x 0,01

= 1675,98 x 0,01

= 16,7598 

(675,98 + 888,66 + 111,34) x 0,01

= (675,98 + [888,66 + 111,34]) x 0,01

= (675,98 + 1000) x 0,01

= 1675,98 x 0,01

= 16,7598 

\(\frac{4}{15}+\frac{8}{13}+\frac{11}{15}+\frac{5}{13}\)

\(=\left(\frac{4}{15}+\frac{11}{15}\right)+\left(\frac{8}{13}+\frac{5}{13}\right)\)

\(=\frac{15}{15}+\frac{13}{13}\)

\(=1+1\)

\(=2\)

Chúc bạn học tốt nha !!! 

\(\frac{4}{15}+\frac{8}{13}+\frac{11}{15}+\frac{5}{13}\)

\(=\left(\frac{4}{15}+\frac{11}{15}\right)+\left(\frac{8}{13}+\frac{5}{13}\right)\)

\(=1+1\)

\(=2\)

=(4/15+11/5)+(8/13+5/13)

=37/15+1=52/15

k mink nha