2. (8% * 40+28% * 0.06)/(40+60) *100% = 3.2168% (Are you sure 40 kg and 60 g are different units? )

3.(60%*200+30%*300)/(200+300)* 100%=42%

4.48/[(4- 1)/(4+ 1)]=80

5.(980-28) * [5/(2+5)] = 680 ... sheep

980-680 = 300 ... cattle

6.960*(3/4)/3/(2/3)=360

7. 10/( 1/3- 1/4)*( 1- 1/3- 1/4)=50

8. 1/4 A =2/5 B, which means 5/8 a = B.

120/( 1-5/8)*( 1+5/8)=52

9.49.5/( 1- 1/ 10)/( 1+ 1/ 10)=50

10.( 1-2/3)*400/(2/3-3/5)=2000

1 1. Cut 4 segments and expose 8 segments.

1 13.04/8*5*7.8=55 1.07

12.27/3=9 9*9*9=729

13. Length * width+length * height = 209 209 =19 *1= (2+17) *11.

[209+(2 * 17)] * 2 = 486 ... Surface area

2 *17 *11= 374 ...

16.4*3.9/(2.5+4)=2.4

17.5%*500/2%-500=750

18.7/20 1 1/20

19.5:8 8:5

20.7/2 1

2 1. Product of external terms = product of internal terms.

1/4.8=5/24

22.m Zinc =(60-6)*(5/9)=30

M copper =60-30=30

M copper: m zinc = 1: 1.

23. English: Chinese: Math = 18: 17:20

English 275*( 18/55)=90.

Language 275*( 17/55)=85

Math 275*(20/55)= 100

24. The speed ratio between Party A and Party B is 3: 2.

18/(3/5-2/5) = 90 ... full distance.

90/6*(2/3)= 10