a) \(3.5^2+15.2^2-26\div2\)

= 3.25 + 15.4 - 13

= 75 + 60 - 13

= 135 - 13

= 122

b) \(5^3.2-100\div4+2^3.5\)

= 125.2 - 25 + 8.5

= 250 - 25 + 40

= 225 + 40

= 265

c)\(6^2\div9+50.2-3^3.33\)

= 36 : 9 + 100 - 9.33

= 4 + 100 - 297

= 104 - 297

= -193

d)\(3^2.5+2^3.10-81\div3\)

= 9.5 + 8.10 - 27

= 45 + 80 - 27

= 125 - 27

= 98

e) \(5^{13}\div5^{10}-25.2^2\)

= 5³ - 25.4

= 125 - 100

= 25

f) \(20\div2^2+5^9\div5^8\)

= 20 : 4 + 5

= 5 + 5

= 10

Đáp Án

a)52:4x3+2x52

=13x3+2x52

=39+104

=143

b)5x42-18:32

=100-0.5625

=99.4375

của bạn nha

a: \(\dfrac{-7}{12}=\dfrac{-7\cdot5}{12\cdot5}=\dfrac{-35}{60};\dfrac{-1}{-15}=\dfrac{1}{15}=\dfrac{4}{60};\dfrac{-5}{4}=\dfrac{-5\cdot15}{4\cdot15}=-\dfrac{75}{60}\)

\(\dfrac{3}{-5}=\dfrac{-3}{5}=\dfrac{-3\cdot12}{5\cdot12}=-\dfrac{36}{60}\)

mà -75<-36<-35<4

nên \(-\dfrac{75}{60}< -\dfrac{36}{60}< -\dfrac{35}{60}< \dfrac{4}{60}\)

=>\(\dfrac{-5}{4}< \dfrac{3}{-5}< \dfrac{-7}{12}< \dfrac{-1}{-15}\)

b: \(\dfrac{-8}{25}+\dfrac{22}{23}+\dfrac{-17}{25}\)

\(=\left(-\dfrac{8}{25}-\dfrac{17}{25}\right)+\dfrac{22}{23}\)

\(=-1+\dfrac{22}{23}=-\dfrac{1}{23}\)

a: \(25\cdot2^3-\left\lbrack164-\left(12-4\right)^2\right\rbrack+10\cdot2018\)

\(=25\cdot8-\left\lbrack164-8^2\right\rbrack+10\cdot2018\)

=200-(164-64)+20180

=20380-100

=20280

b: \(100:\left\lbrace250:\left\lbrack450-\left(4\cdot5^3-2^2\cdot25\right)\right\rbrack\right\rbrace\)

=100:{250:[450-(4*125-4*25)]}

=100:{250:[450-(500-100)]}

=100:{250:[450-400]}

=100:{250:50}

=100:5

=20

a, 36:{336:[200–(12+8.20)]}

= 36:{336:[200–(12+160)]}

= 36:{336:[200–172]}

= 36:{336:28}

= 36:12 = 3

b, {145–[130–(246–236)]:2}.5

= {145–[130–10:2]}.5

= {145–130}.5

= 20.5 = 100

c, 100:{250:[450–(4. 5 3 – 2 2 .25]}

= 100:{250:[450–400]}

= 100:{250:50}

= 100:5 = 20

d, 798+100:[16–2.( 5 2 –22)]

= 798+100:10

= 798+10 = 808

e, (6954+1525:5+47.19).(29–58.2)

= (6954+1525:5+47.19).0 = 0

f,  2 4 .157– 2 4 .58+16

= 16.(157–58+1) = 1600

1.a. 86+357+14 = (86+14)+357 = 100+357 = 457

b. 72+69+128 = (72+128) +69 = 200+69 = 269

c. 25.5.4.27.2 = (25.4).(5.2).27=100.10.27=1000.27=27000

d. 28.64+28.36=28.(64+36)=28.100=2800

2. a. 135+360+65+40= (135+65)+(360+40)=200+400=600

b. 463+318+137+22 = (463+137)+(318+22)=600+340=940

c. = (20+30)+(21+29)+...+(24+26)+25

= 50+50+50+50+25

= 225

Số số hạng của tổng đó là:

( 23 - 2) :1 + 1 = 22 (số)

Tổng đó là: (23+2) x 22 :2 = 275

Cách tính:

Số số hạng = ( Số cuối - Số đầu) : Khoảng cách + 1

Tính tổng = ( Số cuối + Số đầu) x Số số hạng : 2