42 nha

X x 62 + X x 38 = 4200

X x (62+38)=4200

X=4200:100=42

Đáp số : 42

X x 62 + X x 38 = 4200

X x ( 62 + 38 ) =   4200

X x    100        =   4200

X                    = 4200: 100

X                    =   42

=> x . ( 62 + 38 ) = 4200

=> x . 100 = 4200

=> x = 4200 : 100

=> x = 42

\(x\times62+x\times38=4200\)

\(x\times\left(62+38\right)=4200\) 

\(x\times100=4200\)

\(x=4200:100\)

\(x=42\)

\(x\times62+x\times38=4200\)

\(x\times\left(62+38\right)=4200\)

\(x\times100=4200\)

\(x=4200\div100=42\)

X x 62 + X x 38 = 4200

X x (62 + 38) = 4200

X x 100 = 4200

X = 4200 : 100

X = 42.

x(62 + 38) = 4200

100x = 4200

x = 4200 : 100

x = 42 

a) 1400 : 20 - (17 + x) = 20

70 - (17 + x) = 20

17 + x = 70 - 20

17 + x = 50

x = 50 - 17

x = 33

b) 8 \(\times\) (x + 15) = 640

x + 15 = 640 : 8 

x + 15 = 80

x = 80 - 15

x = 65

c) x \(\times\) 62 + x \(\times\) 38 = 4200

x  \(\times\) (62 + 38) = 4200

x \(\times\) 100 = 4200

x = 4200 : 100

x = 42

d) x \(\times\) 186 - x \(\times\) 86 = 3400

x \(\times\) (186 - 86) = 3400

x \(\times\) 100 = 3400

x = 3400 : 100

x = 34 

Ta có:

x*62+x*48=4200.

x*(62+48)=4200.

x*110=4200.

x*11=420.

x=420/11.

Vậy x=420/11.

X x 62 +X x 48=4200

(62+48)x X     =4200

110 x X         =4200

         X        =4200:110

        X        =38,18

k nha

X x 62 + X x 48 = 4200 

X x ( 62 + 48 )   = 4200

X x 110             = 4200

X                      = 4200 : 110

X                      = \(\frac{420}{11}\)

~ Chúc học tốt ~

Ai ngang qua xin để lại 1 L - I - K - E 

X x 62 +X x 48 = 4200

=> X x (62+48)=4200

=> X x 110=4200

=> X=4200:110

=> X=\(\frac{420}{11}\)

Xx62+Xx48 = 4200

Xx(62+48)=4200

Xx110=4200

X=4200:110

X=38(18)

X×62+X×48=4200

X×(62+48)=4200

X×110=4200

X =4200:110

X=\(\frac{420}{11}\)

X×62+X×48=4200

\(x\times\left(62+48\right)=4200\)

\(x\times110=4200\)

\(x=4200:110\)

\(x=\dfrac{420}{11}\)

X x 62 + X x 48= 4200

X x(62 + 48)= 4200

X x 110= 4200

X = 4200 : 110

X = 4200/ 110= 420/ 11

Dxw6d

X x 186 - X x 38 = 4200

 X x ( 186 - 38 ) = 4200

           X x 148 = 4200

                  X   = 4200 : 148

                  X   = \(\frac{1050}{37}\)

X x ( 186 - 38 ) = 4200

X x   148           = 4200

X                       =4200 : 148

X                       = ....

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