\(\dfrac{2}{3}+\dfrac{1}{5}.\dfrac{10}{7}=\dfrac{2}{3}+\dfrac{10}{35}=\dfrac{70}{105}+\dfrac{30}{105}=\dfrac{100}{105}=\dfrac{50}{21}\)

a) Ta có: \(\dfrac{2}{3}+\dfrac{1}{5}\cdot\dfrac{10}{7}\)

\(=\dfrac{2}{3}+\dfrac{2}{7}\)

\(=\dfrac{14}{21}+\dfrac{6}{21}\)

\(=\dfrac{20}{21}\)

\(\dfrac{7}{12}-\dfrac{27}{7}.\dfrac{1}{8}=\dfrac{7}{12}-\dfrac{27}{56}=\dfrac{392}{672}-\dfrac{324}{672}=\dfrac{68}{672}=\dfrac{17}{168}\)

`a)3/5+13/5-5/9-3/7`

`=16/5-5/9-3/7`

`=698/315`

3/5 + 13 /5 -5/9 - 3/7 = 698/315

a: Ta có: \(\left(8\cdot5^7+5^6-5^5\right):5^5\)

\(=8\cdot5^2+5-1\)

\(=200+4=204\)

b: Ta có: \(\left(9^{30}-27^{19}\right):3^{57}+\left(125^9-25^{12}\right):5^{24}\)

\(=3^{60}:3^{57}-3^{57}:3^{57}+5^{27}:5^{24}-5^{24}:5^{24}\)

\(=27-1+125-1\)

=150

a. (8,5⁷ - 5⁵ + 5⁶) : 5⁵

= (8,5⁷ : 5⁵) - (5⁵ : 5⁵) + (5⁶ : 5⁵)

= 1,7² - 1 + 5

= 2,89 - 1 + 5

= 6,89

b. (9³⁰ - 27¹⁹) : 3⁵⁷ + (125⁹ - 25¹²) : 5²⁴

= (9³⁰ : 3⁵⁷) - (27¹⁹ : 3⁵⁷) + (125⁹ : 5²⁴) - (25¹² : 5²⁴)

= 3³ - 1 + 125 - 1

= 27 - 1 + 125 - 1

= 150

c. (10¹² + 5¹¹ . 2⁹ - 5¹³ - 2⁸) : 4 . 5⁵ . 10⁶

= (10¹² + 2,5 , 10¹⁰ - 5¹³ - 2⁸) : 1,25 . 10¹⁰

= (10¹² : 1,25 . 10¹⁰) + (2,5 . 10¹⁰ : 1,25 . 10¹⁰) - (5¹³ : 1,25 . 10¹⁰) - (2⁸ : 1,25 . 10¹⁰)

= 80 + 2 - \(\dfrac{25}{256}\) - \(\dfrac{1}{48828125}\)

= 81,90234373 \(\approx\) 82

a) $371+731-271-531$

$=(371-271)+(731-531)$

$=100+200$

$=300$

b) $57+58+59+60+61-17-18-19-20-21$

$=(57-17)+(58-18)+(59-19)+(60-20)+(61-21)$

$=40+40+40+40+40$

$=40\cdot5$

$=200$

c) $9-10+11-12+13-14+15-16$

$=(9-10)+(11-12)+(13-14)+(15-16)$

$=-1+(-1)+(-1)+(-1)$

$=-1\cdot4$

$=-4$

$\text{#}Toru$

a: =371-271-531+731=100+200=300

b: =-321-28-327+27

=-350-300

=650

c: =-424-371+424+29=-342

d: =-249+248=-1

a)371+(-271)+(-531)+731=300

b)-312+(-327+(-28)+27=650

c)-424+(-371)-(-424)-(-29)=-342

d)-249+197+248+(-197)=-1

e)3+(-5)+(-9)+11+(-13)=-13

g)-8+10+(-12)+14+(-16)+18=6

8-3-+7=12

-5-9+12=-2

7+9-3=13

-3+8-11=-6

8-3+7=12

(-5)-9+12=-2

7-9-3=-5

(-3)+8-11=-6

a, 8-(3-7)

=8-(-4)

=4

b,(-5)-(9-12)

=(-5)-(-3)

=(-8)

c,7-(-9)-3

=(-2)-3

=-1

d.(-3)+8-11

=5-11

=6

a) 600000

c) -40

e) 1922

b) -35

d) 350

Dài thế bro:)

chia ra

a/=-600000

b/=1200

c/-40

d/350

e/-508

:)

\(\dfrac{3}{5}+\dfrac{13}{25}-\dfrac{5}{9}-\dfrac{3}{7}\)

\(=\dfrac{15}{25}+\dfrac{13}{25}-\dfrac{35}{63}-\dfrac{27}{63}\)

\(=\dfrac{28}{25}-\dfrac{62}{63}=\dfrac{214}{1575}\)

bằng 214/1575