3.Tính giá trị biểu thức(giá trị là số tự nhiên) a.118:4-18:4 b.3500:123+2035:123 c.987:110+654:110-321:110

Đáp án:

a,`118 : 4 – 18 : 4`

`= 118 : 4/1 – 18 : 4/1`

`= 118 × 1/4 – 18 × 1/4`

`= (118 – 18) × 1/4`

`= 100 × 1/4`

`= 100/4 `

`= 25`

b,`3500 :  123 + 2035 : 123`

`= 3500 : 123/1 + 2035 : 123/1`

`= 3500 × 1/123 + 2035 × 1/123`

`= (3500 + 2035) × 1/123`

`= 5535 × 1/123`

`= 5535/123`

`= 45`

c,`987 : 110 + 654 : 110 – 321 : 110`

`= 987 : 110/1 + 654 : 110/1 – 321 : 110/1`

`= 987 × 1/110 + 654 × 1/110 – 321 × 1/110`

`= (987 + 654 – 321) × 1/110`

`= 1320 × 1/110`

`= 1320/110`

`= 12`