Here are the solutions to the problems in the image:

Penjumlahan (Addition):

a. $0.23 + 0.02 = 0.25$
b. $0.34 + 0.28 = 0.62$
c. $3.45 + 2.17 = 5.62$
d. $0.58 + 0.74 = 1.32$

Pengurangan (Subtraction):

a. $0.52 - 0.25 = 0.27$
b. $0.95 - 0.49 = 0.46$
c. $1.25 - 0.30 = 0.95$
d. $80.45 - 39.67 = 40.78$

Would you like any additional explanations or details?

Here are 5 related questions to expand your practice:

1. What is $2.34 + 3.67$?
2. How do you solve $1.98 - 0.56$?
3. Calculate $0.75 + 1.25$.
4. Solve $7.8 - 4.5$.
5. What is $3.6 + 2.8$?

Tip: When adding or subtracting decimals, always align the decimal points to ensure accuracy!