Question

Bài 1 : tính nhanh a ) 25 × 8 × 4 × 125 b ) 17 × 173 - 17 × 73 c ) 46 × ( 2 + 3 )

Answer 1

`a)`

`25 × 8 × 4 × 125`

`= (25 xx 4) xx ( 8 xx 125)`

`= 100 xx 1000`

`=100000`

`b)`

`17 × 173 - 17 × 73`

`= 17 × (173 -73)`

`=17 xx 100`

`=1700`

`c)`

` 46 × ( 2 + 3 )`

`=46 xx 5`

`= 230`

 

 

 

Answer 2

a \(\left(25\times4\right)\times\left(125\times8\right)=100\times1000=100000\)

b \(17\times\left(173-73\right)=17\times100=1700\)

c \(46\times5=230\)

Answer 3

a)25x8x4x125        b)17x173-17x73    c)46x(2+3)

=(25x4)x(8x125)     =17x(173-73)         =46x5

=100x1000             =17x100                 =230

=100000                 =1700