Ta có:

45=5.3²

195=5.3.13

  ƯCLN(45;195)=5.3=15

ƯC(45;195)=Ư(15)={1;3;5;15}

45=5.3²

195=5.3.13

  ƯCLN(45;195)=5.3=15

ƯC(45;195)=Ư(15)={1;3;5;15}

\(\frac{x-241}{17}+\frac{x-220}{19}+\frac{x-195}{21}+\frac{x-166}{23}=0\)

\(\Leftrightarrow\frac{x-258}{17}+\frac{x-258}{19}+\frac{x-258}{21}+\frac{x-258}{23}=-10\)

\(\Leftrightarrow\left(x-258\right)\left(\frac{1}{17}+\frac{1}{19}+\frac{1}{21}+\frac{1}{23}\right)=-10\)

\(.....................\)

đến đây thì dễ rồi :)

mk không giải được phần sau

\(Tính:\frac{1}{17}+\frac{1}{19}+\frac{1}{21}+\frac{1}{23}=?\Rightarrow x-258=\left(-10\right):?\)

mik tl dùm nek 315:45=7

                      195:15=13

315 : 45 = 7

195 : 15 = 13

\(\left[195-\left(3x-27\right)\right]\cdot39=4212\)

\(\Rightarrow\left(195-3x+27\right)\cdot39=4212\)

\(\Rightarrow\left(-3x+222\right)\cdot39=4212\)

\(\Rightarrow-3x+222=\dfrac{4212}{39}\)

\(\Rightarrow-3x+222=108\)

\(\Rightarrow3x=222-108\)

\(\Rightarrow3x=114\)

\(\Rightarrow x=\dfrac{114}{3}\)

\(\Rightarrow x=38\)

=>[195-(3x-27)]=4212:39=108

=>3x-27=195-108=87

=>3x=27+87=114

=>x=38

195 :45 -60 :45 =(195-60):45 = 135 :60 =3

40:24+8:24=(40+8):24=48:24 =2

705 :45 -336 :45 = (705-336):45 = 369 :45 = 41/5

195 : 45 - 60 : 45

= (195-60):45

=135:45

=3

40 : 24 + 8 : 24

= (40+8) : 24

= 48:24

=2

705 : 45 - 336 : 45

=(705-336):45

=369:45

=8,2

\(a,91-5.\left(5+x\right)=61\\ \Rightarrow=5.\left(5+x\right)=30\\ \Rightarrow5+x=6\\ \Rightarrow x=1.\\ b,\left[195-\left(3x-27\right)\right].39=4212\\ \Rightarrow195-\left(3x-27\right)=108\\ \Rightarrow3x-27=87\\ \Rightarrow3x=114\\ \Rightarrow x=38.\)

\(91-5.\left(5+x\right)=61\)

\(\Rightarrow5.\left(5+x\right)=91-61\)

\(\Rightarrow5.\left(5+x\right)=30\)

\(\Rightarrow5+x=\dfrac{30}{5}=6\)

\(\Rightarrow x=6-5=1\)

\(\left[195-\left(3x-27\right)\right].39=4212\)

\(\Rightarrow195-3x+27=\dfrac{4212}{39}=108\)

\(\Rightarrow222-3x=108\)

\(\Rightarrow3x=222-108=114\)

\(\Rightarrow x=\dfrac{114}{3}=38\)

$91-5.\left(5+x\right)=61$

$\Rightarrow 5.\left(5+x\right)=91-61$

$\Rightarrow 5.\left(5+x\right)=30$

⇒5+�=305=6⇒5+x=530​=6

$\Rightarrow x=6-5=1$

$\left[195-\left(3x-27\right)\right].39=4212$

⇒195−3�+27=421239=108⇒195−3x+27=
​4212/39=108

$\Rightarrow 222-3x=108$

$\Rightarrow 3x=222-108=114$

⇒�=1143=38⇒x=114/3
​=38

a,91-5(5+x)=61

=>25+5x=91-61=30

=>5x=30-25=5

=>x=1

b,\([\left(x+34\right)-50]\)x2=56

=>(x+34)-50=56:2=28

=>x+34=28+50=78

=>x=78-34=44.

c,1045-\([2015-\left(3x-24\right)]\)=5

=>2015-(3x-24)=1045-5=1040

=>3x-24=2015-1040=975

=>3x=975+24=999

=>x=999:3=333

d,\([195-\left(3x-27\right)]\)x39=4212

=>195-(3x-27)=4212:39=108

=>3x-27=195-108=87

=>3x=87+27=117

=>x=39

e,30-3(x-2)=18

=>30-3x+6=18

=>30-3x=18-6=12

=>3x=30-12=18

=>x=18:3=6

a) \(...\Rightarrow5\left(5+x\right)=91-61=30\)

\(\Rightarrow\left(5+x\right)=30:5=6\Rightarrow x=6-5=1\)

b) \(...\Rightarrow\left(x+34\right)-50=56:2=28\)

\(\Rightarrow\left(x+34\right)=28+50=78\Rightarrow x=78-34=44\)

c) \(...\Rightarrow2015-\left(3x-24\right)=1045-5=1040\)

\(\Rightarrow\left(3x-24\right)=2015-1040=975\)

\(\Rightarrow3x=975+24=999\Rightarrow x=999:3=333\)

d) \(...\Rightarrow195-\left(3x-27\right)=4212:39=108\)

\(\Rightarrow\left(3x-27\right)=195-108=87\)

\(\Rightarrow3x=87+27=114\Rightarrow x=114:3=38\)

e) \(...\Rightarrow3\left(x-2\right)=30-18=12\Rightarrow x-2=12:3=4\)

\(\Rightarrow x=4+2=6\)

Tổng của 2 số đó lúc đầu là :

195 - 12 = 183 

Số bé là : 

( 183 - 45) : 2 = 69

Số lớn là : 

69 + 45 = 114 

ĐS ..........

số thứ nhất là : 69

số thứ hai là: 114

số thứ nhất là  : 69

số thứ hai là: 114