478 - (500-25*3) (300+160:4) : 2 500 + (400-160+40) (870-240*3) : 5 (120-80) : (100:25) 100-32 * (87-84) 280-140*2+7 (81:3) : (9*3) по действиям

1) 478 - (500-25*3) = 53

1. 25*3=75

2.500-75=425

3.478-425=53

2) (300+160:4) : 2=170

1. 160:4=40

2. 300+40=340

3.340:2=170

3) 500 + (400-160+40) = 780

1. 400-160=240

2. 240+40=280

3. 500+280=780

4) (870-240*3) : 5=30

1.240*3=720

2.870-720=150

3.150:5=30

5) (120-80) : (100:25) = 10

1. 120-80=40

2. 100:25=4

3. 40:4=10

6) 100-32 * (87-84) = 71

1. 87-84=3

2. 32-3=29

3. 100-29=71

7) 280-140*2+7=7

1. 140*2=280

2. 280-280=0

3. 0+7=7

8) (81:3) : (9*3) = 1

1. 81:3=27

2. 9*3=27

3. 27:27=1