1/200

164.4

76.8

175.75

2592

= 164,8 x 3 x 1,5 - 64,8 x 1,5 - 64,8 x 3 

= 1,5 x ( 164,8 x 3 - 64,8 - 64,8 x 2 ) 

= 1,5 x 300 

= 450 

164,8 \(\times\) 4,5 - 64,8 \(\times\) 1,5 - 64,8 \(\times\) 3

= 164,8 \(\times\) 4,5 - ( 64,8 \(\times\) 1,5 + 64,8 \(\times\) 3)

=164,8 \(\times\) 4,5 - 64,8 \(\times\) ( 1,5 + 3)

= 164,8 \(\times\) 4,5 - 64,8 \(\times\) 4,5

= 4,5 \(\times\) (164,8 - 64,8)

= 4,5 \(\times\)  100

= 450

a)<=>2/7:(13/24+5/24)   b)<=>15/24-9/24-4/24       c)=7.5.39/13.14.15

<=>2/7:3/4                        <=>2/24=1/12                      =3/2.3

<=>2/7x4/3                                                                    =1/2

<=>8/21                                     

a. \(\frac{2}{7}:\frac{13}{24}+\frac{2}{7}:\frac{5}{24}\)

= \(\frac{2}{7}:\left(\frac{13}{24}+\frac{5}{24}\right)\)

= \(\frac{2}{7}:\frac{3}{4}\)

= \(\frac{8}{21}\)

b. \(\frac{15}{24}-\frac{3}{8}-\frac{1}{6}\)

= \(\frac{15}{24}-\frac{9}{24}-\frac{4}{24}\)

= \(\frac{2}{24}=\frac{1}{12}\)

c. \(\frac{7}{13}.\frac{5}{14}.\frac{39}{15}\)

= \(\frac{7.5.3.13}{13.2.7.3.5}\)

= \(\frac{1}{2}\)

\(\frac{x+24}{16}=\frac{45}{24}\)

<=> \(\frac{\left(x+24\right)x24}{16x45}\)

<=> \(\frac{\left(x+24\right)x24}{720}\)

<=> x+24 = 720 : 24

<=> x+24 = 30

<=> x       = 30-24

<=>x        = 6

 vậy x=6

=>(x+24)x24=45x16

=>(x+24)x24=720

=>x+ 24=30

=>x=6

Tinh nhanhcác bann

  64,8 x 4,2 + 32,4 x 9,6 + 16,2 x 4

= 4 x ( 64,8 + 16,2 ) + 32,4 x 9,6

= 4 x 81 + 32,4 x 9,6

= 324 + 311,04

= 635,04

\(\frac{2}{7}:\frac{13}{24}+\frac{2}{7}:\frac{5}{24}\)

\(=\frac{2}{7}x\frac{24}{13}+\frac{2}{7}x\frac{14}{5}=\frac{2}{13}x\frac{24}{7}+\frac{2}{5}x\frac{24}{7}\)

\(=\frac{24}{7}x\left(\frac{2}{13}+\frac{2}{5}\right)=\frac{24}{7}x\frac{36}{65}=\frac{864}{455}\)

=48/91+48/35

=864/455

   study well

  k nha

  mk xin cảm ơn mọi người

\(2-\left[\left(5\frac{5}{24}+x\right)-7\frac{5}{24}\right]=0\)

\(\left[\left(\frac{125}{24}+x\right)-\frac{173}{24}\right]=2-0=2\)

\(\frac{125}{24}+x-\frac{173}{24}=2\)

\(\frac{125}{24}-\frac{173}{24}+x=2\)

\(\frac{-48}{24}+x=2\)

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

\(x=4\)

cbfgdh

\(x=\dfrac{750}{25\%}=3000\)

3000