Question

28см+3см 5см+1дм 7см-4дм 2см

Answer 1

31см, 15см или 1,5 дм,-33см, 2см

Answer 2

Let's solve the arithmetic expressions you provided:

1. 28 cm + 3 cm: The sum of 28 cm and 3 cm is 31 cm.

2. 5 cm + 1 dm: To add centimeters and decimeters, we need to convert them to the same unit. Since 1 dm is equal to 10 cm, we have: 5 cm + 10 cm = 15 cm.

3. 7 cm - 4 dm: Similarly, we need to convert the units to the same type. Since 1 dm is equal to 10 cm, we have: 7 cm - 4 dm (4 dm = 40 cm) = 7 cm - 40 cm = -33 cm.

4. 2 cm: There's no operation specified for this expression, so we can consider it as a standalone measurement. Therefore, it represents 2 cm.

To summarize:

1. 28 cm + 3 cm = 31 cm.
2. 5 cm + 1 dm = 15 cm.
3. 7 cm - 4 dm = -33 cm.
4. 2 cm = 2 cm.