a) 220 - [3² . 3³ - (12 - 7⁰) ²]

= 220 - [9 . 27 - (12 - 1)²]

= 220 - [9 . 27 - 11²]

= 220 - [9 . 27 - 121]

= 220 - [243 - 121]

= 220 - 122

= 98

b) [504 - (5² . 8 + 70) : 3³ + 6] : 125

= [504 - (25 . 8 + 70) : 27 + 6] : 125

= [504 - (200 + 70) : 27 + 6] :125

= [504 - 270 : 27 + 6] : 125

= [504 - 10 + 6] : 125

= [494 + 6] : 125

= 500 : 125

= 4

c) 27 . 2³ + 4 . 3² - 5 . 12⁰

= 27 . 8 + 4 . 9 - 5 . 1

= 216 + 36 - 5

= 252 - 5

= 247

d) 316 - (5. 2 . 2² + 2⁴) : 2³ - 3 . 2³

= 316 - (5 . 2 . 4 + 16) : 8 - 3 . 8

= 316 - (40 + 16) : 8 - 3 . 8 

= 316 - 56 : 8 - 3 . 8 

= 316 - 7 - 3 . 8

= 316 - 7 - 24

= 309 - 24

= 285

=27.8+4.9-5.1

=216+36-4

=216+32

=248

(9.8-12-5.12).(1+2+3+4+5)

=(72-12-60).(1+2+3+4+5)

=0.(1+2+3+4+5)

=0

(9.8-12-5.12).(1+2+3+4+5)

=( 70 - 70 ) . 15

= 0 . 15

=0

ko hiểu câu hỏi cho lắm bạn ạ 

i don't know

bấm máy là ra

Hoa cả mắt

(27.2⁶.625):(5³.64.3²)

=(3³.2⁶.5⁴):(5³.2⁶.3²)

=3.5=15

\(\frac{1}{1.2}+\frac{3}{2.5}+\frac{7}{5.12}+\frac{13}{12.25}+\frac{21}{25.46}\)

\(=1-\frac{1}{2}+\frac{1}{2}-\frac{1}{5}+\frac{1}{5}-\frac{1}{12}+\frac{1}{12}-\frac{1}{25}+\frac{1}{25}-\frac{1}{46}\)

\(=1-\frac{1}{46}\)

\(=\frac{45}{46}\)