21. 25+18+(-23)= 20

22. -65+(-2)+9= -58

23. 80+15+(-26)= 69

24. -5+4+(-27)= 18

25. -29+12+44= 27

30. 30+(-9)+1= 22

32. 51+ (-21)+-12)= 18

24 is wrong.

The others are right.

-28

Right.

To solve these arithmetic problems, you need to perform addition and subtraction operations. Let's break down each equation and explain how to get the answer:

21. 25 + 18 + (-23) = 20
To solve this equation, follow these steps:
- Start with 25.
- Add 18 to get 43.
- Subtract 23 from 43 to get the final answer, which is 20.

22. -65 + (-2) + 9 = -58
To solve this equation, follow these steps:
- Start with -65.
- Add -2 to get -67.
- Add 9 to -67 to get the final answer, which is -58.

23. 80 + 15 + (-26) = 69
To solve this equation, follow these steps:
- Start with 80.
- Add 15 to get 95.
- Subtract 26 from 95 to get the final answer, which is 69.

24. -5 + 4 + (-27) = 18
To solve this equation, follow these steps:
- Start with -5.
- Add 4 to get -1.
- Add -27 to -1 to get the final answer, which is 18.

25. -29 + 12 + 44 = 27
To solve this equation, follow these steps:
- Start with -29.
- Add 12 to get -17.
- Add 44 to -17 to get the final answer, which is 27.

30. 30 + (-9) + 1 = 22
To solve this equation, follow these steps:
- Start with 30.
- Add -9 to get 21.
- Add 1 to 21 to get the final answer, which is 22.

32. 51 + (-21) + (-12) = 18
To solve this equation, follow these steps:
- Start with 51.
- Add -21 to get 30.
- Add -12 to 30 to get the final answer, which is 18.

Remember that adding a negative number is the same as subtracting that number. Similarly, subtracting a negative number is the same as adding that number.