Question

Thực hiện phép tính bằng cách hop lý nhát

a, 277+113+323+87.                  b,185+434+515+266+155

                                                        d, 4×36×25×50

C, 8×12×125×2

Answer 1

a, 277 + 113 + 323 + 87

= ( 277 + 323 ) + ( 113 + 87 )

= 600 + 200

= 800

b, 185 + 434 + 515 + 266 + 155

= ( 185 + 515 ) + ( 434 + 266 ) + 155

= 700 + 700 + 155

= 1400 + 155

= 1555

c, 8 . 12 . 125 . 2

= ( 125 . 8 ) . ( 12 . 2 )

= 1000 . 24

= 24000

d, 4 . 36 . 25 . 50

= ( 4 . 25 ) . ( 36 . 50 )

= 100 . 1800

= 180000

Answer 2

a, 277 + 113 + 323 + 87

= ( 277 + 323 ) + ( 113 + 87 )

= 600 + 200

= 800

b, 185 + 434 + 515 + 266 + 155

= ( 185 + 515 ) + ( 434 + 266 ) + 155

= 700 + 700 + 155

= 1400 + 155

= 1555

c, 8 . 12 . 125 . 2

= ( 125 . 8 ) . ( 12 . 2 )

= 1000 . 24

= 24000

d, 4 . 36 . 25 . 50

= ( 4 . 25 ) . ( 36 . 50 )

= 100 . 1800

= 180000