\(\frac{18}{27}-\frac26\)

\(=\frac23-\frac13=\frac{2-1}{3}=\frac13\)

\(\frac{37}{12}-3=\frac{37}{12}-\frac{36}{12}=\frac{37-36}{12}=\frac{1}{12}\)

\(5-\frac{14}{3}=\frac{15}{3}-\frac{14}{3}=\frac{15-14}{3}=\frac13\)

\(\frac{10}{21}:\frac23=\frac{10}{21}\times\frac32=\frac{30}{42}=\frac57\)

\(\frac35:\frac34=\frac35\times\frac43=\frac33\times\frac45=\frac45\)

\(\frac25:\frac{3}{10}=\frac25\times\frac{10}{3}=\frac{20}{15}=\frac43\)

\(\frac38:\frac94=\frac38\times\frac49=\frac{12}{72}=\frac16\)

\(\frac{8}{21}:\frac47=\frac{8}{21}\times\frac74=\frac{7}{21}\times\frac84=\frac23\)

\(\frac85:\frac{15}{8}=\frac85\times\frac{8}{15}=\frac{64}{75}\)

5

số số hạng:

(310-5):5+1=62(số)

tổng:

(310+5) x 62 : 2=9765

5+10+15+20.......+300+305+310=9765

a: Ta có: \(60-3\left(x-2\right)=51\)

\(\Leftrightarrow3\left(x-2\right)=9\)

\(\Leftrightarrow x-2=3\)

hay x=5

b: Ta có: \(4x-20=2^5:2^3\)

\(\Leftrightarrow4x=24\)

hay x=6

c, 10 + 2 . x = 4⁵ : 4³

    10 + 2 . x = 4²

    10 + 2 . x = 16

            2 . x = 16 - 10

            2 . x = 6

                 x = 6 : 2

                 x = 3

             Vậy x = 3.

Đây nha bạn!!!

Chúc bạn học tốt!!!

a.(x + 125) : 312 = 14 (dư 300)

x+125 = 14 x 312 + 300

x+125 = 4 668

x= 4 668 - 125

x=4 543

b.(x-234):23=128 (dư 21)

    x-234=128 x 23 + 21

    x-234=2 965

    x=2 965 + 234

    x=3 199

c.(x-24) x 2020=2020x33

   (x-24)x2020=66 660

    x-24=66 660:2020

    x-24=33

    x=33+24

    x=57

d.5 x (x+2019)=3800 x 5

   5 x (x+2019)=19 000

   x+2019=19000:5

   x+2019=3800

   x=3800-2019

   x=1 781

HẾT=)))

a.(x + 125) : 312 = 14 (dư 300)

x+125 = 14 x 312 + 300

x+125 = 4 668

x= 4 668 - 125

x=4 543

b.(x-234):23=128 (dư 21)

    x-234=128 x 23 + 21

    x-234=2 965

    x=2 965 + 234

    x=3 199

c.(x-24) x 2020=2020x33

   (x-24)x2020=66 660

    x-24=66 660:2020

    x-24=33

    x=33+24

    x=57

d.5 x (x+2019)=3800 x 5

   5 x (x+2019)=19 000

   x+2019=19000:5

   x+2019=3800

   x=3800-2019

   x=1 781

HẾT=)))

Dat \(S=5+10+15+...+310=5x\left(1+2+3+...+62\right)=5x\frac{\left(62+1\right)x62}{2}=9765\)

cach 2

\(S=\frac{\left(310+5\right)x62}{2}=9765\)

9765

tick mình nha 

số cuối + số đâu x khoảng cách là ra.

`#040911`

`a)`

\(37 \times 7 - 17 \times 11 + 13 \times 37 + 17 \times 21\)

`= 37 \times (7 + 13) + 17 \times (21 - 11)`

`= 37 \times 20 + 17 \times 10`

`= 10 \times (37 \times 2 + 17)`

`= 10 \times 91`

`= 910`

`b)`

\(5^5 \times 5^2 \div 5^4 - 2^8 \div 2^4\)

`=`\(5^{5+2-4}-2^{8-4}\)

`= 5^3 - 2^4`

`= 125 - 16`

`= 109`

`c)`

\(3^{11}\times12+3^{12}\times5-3^{14}\)

`=`\(3^{11}\times\left(12+3\times5-3^3\right)\)

`=`\(3^{11}\times\left(12+15-27\right)\)

`=`\(3^{11}\times0=0\)

a) = 259 - 187 + 481 + 357

= 910

b) = 5⁷ : 5⁴ - 2⁴

= 5³ - 2⁴ 

= 125 - 16

= 109