\(a,25.\left(7-27\right)+27.25\)

\(=25.7-27+27.25\)

\(=27.\left(25+25\right)-7\)

\(=27.50-7=135-7=128\)( ko chắc )

\(b,\left(-3\right)^2.\left(-2\right)^3\)

\(=9.\left(-8\right)=-72\)

lam cho minh cai

có một câu nữa : d)211/6 : (-4/5) - 271/6 : (-4/5)

a)13/2     b)9,925  c)-1  d)

To

(Vì bạn phân số thành một hàng nên có thể mình sẽ giải sai)

a, \(19\dfrac{1}{3}\) . \(\dfrac{3}{7}\) - \(33\dfrac{1}{3}\)

= \(\dfrac{58}{3}\) . \(\dfrac{3}{7}\) - \(\dfrac{100}{3}\)

= \(\dfrac{58.1}{1.7}\) - \(\dfrac{100}{3}\)

= \(\dfrac{58}{7}\) - \(\dfrac{100}{3}\) = \(\dfrac{174}{21}-\dfrac{700}{21}\)

= \(\dfrac{-526}{21}=-25\dfrac{1}{21}\)

Thực hiện phép tính ( bằng cách hợp lí nếu có thể ) 

A. 2/3 - (- 1/4)+3/5-(+7/45)-(-5/9)+1/12+1/39 

B. 6.(-2/3)^2 - 3(-2/3)^2 - 2 : (-3/2)+4

a) 463+318+137+22

 = (463+137)+(318+22)

 =  600+340

 = 940

b) 185.32-32.85

 =  32.(185-85)

 =  32 . 100

 =  3200

c) \(15:\left\{390:\left[500-\left(125+35.7\right)\right]\right\}\)

\(\text{= }15:\left\{390:\left[500-\left(125+245\right)\right]\right\}\)

\(\text{= }15:\left\{390:\left[500-370\right]\right\}\)

\(=15:\left(390:130\right)\)

\(\text{= }15:3\)

\(\text{= }5\)

a)\(463+318+137+22\)

\(=\left(463+137\right)+\left(318+22\right)\)

\(=600+340=940\)

b)\(185.3^2-3^2.85\)

\(=3^2.\left(185-85\right)\)

\(=9.100=900\)

c)\(15:\left\{390:\left[500-\left(125+35.7\right)\right]\right\}\)

\(=15:\left\{390:\left[500-\left(125+245\right)\right]\right\}\)

\(=15:\left\{390:\left[500-370\right]\right\}\)

\(=15:\left\{390:130\right\}\)

\(=15:3=5\)

a) 463 + 318 + 137 + 22 = (463 + 137) + (318 +22) = 600 + 340 = 940

-1/2+ 2/3 - 3/4 + 4/5

trả lời:

-1/2+ 2/3 - 3/4 + 4/5

=13/60