Question

Bài 6: Tính bằng cách hợp lí nhất: a) 35.42 +35.68 + 65.75 + 65.45 
b) 36.28 + 36.82 + 64.69 + 64.41

Answer 1

`a) 35.42 + 35.68 + 65.75 + 65.45`

`= 35.(42 + 68) + 65.(75 + 45)`

`= 35.110 + 65.120`

`= 3850 + 7800`

`= 11650`

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`b) 36.28 + 36.82 + 64.69 + 64.41`

`= 36.(28 + 82) + 64.(69 + 41)`

`= 36. 110 + 64 . 110`

`= 110.(36 + 64)`

`= 110 . 100`

`= 11000`

Answer 2

`35.42 +35.68 + 65.75 + 65.45 `

` = 35 . ( 42 + 68) + 65 . ( 75 + 45)`

` = 35 . 110 + 65 . 120`

` = 3850 + 7800`

` = 11650`

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` 36.28 + 36.82 + 64.69 + 64.41`

` = 36 . ( 28 + 82) + 64 . ( 69 + 41)`

` = 36 . 110 + 64 . 110`

` = (36 + 64). 110`

` = 100. 110`

` = 11000`

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`#BaoL i nh`

Answer 3

Bài 6: Tính bằng cách hợp lí nhất:

a) 35 . 42 + 35 . 68 + 65 . 75 + 65 . 45 

= [35 . (42 + 68)] + [65 . (75 + 45)]

= [35 . 110] + [65 . 120]

=  3850 + 7800

= 11650

b) 36 . 28 + 36 . 82 + 64 . 69 + 64 . 41

= [36 . (28 + 82)] + [64 . (69 + 41)]

= [36 . 110] + [64 . 110]

= 3960 + 7040

= 11000.

Answer 4