Question

70см-3дм= 65м+40дм= 4дм+40см= 1м-78см= 90дм-70дм=

Answer 1

70-3=40см 65+40=50дм1см 4дм+40см=80см

Answer 2

70см-3дм=70-30=40
65м+40дм=650+400=1050
4дм+40см=40+40=80
1м-78см=100-78=22
90дм-70дм=900-700=200

Answer 3

To solve these expressions, we need to remember the conversion factors between different units of length:

1 meter (m) = 100 centimeters (cm) 1 decimeter (dm) = 10 centimeters (cm)

Now let's solve each expression:

1. 70 cm - 3 dm:

• Convert 3 dm to cm: 3 dm x 10 cm/dm = 30 cm
• Subtract 30 cm from 70 cm: 70 cm - 30 cm = 40 cm
• Therefore, 70 cm - 3 dm = 40 cm

2. 65 m + 40 dm:

• Convert 40 dm to cm: 40 dm x 10 cm/dm = 400 cm
• Add 65 m and 400 cm: 65 m + 400 cm = 6500 cm + 400 cm = 6900 cm
• Convert 6900 cm to meters and decimeters: 6900 cm ÷ 100 cm/m = 69 m and 6900 cm - 69 m x 100 cm/m = 90 dm
• Therefore, 65 m + 40 dm = 69 m 90 dm

3. 4 dm + 40 cm:

• Convert 4 dm to cm: 4 dm x 10 cm/dm = 40 cm
• Add 40 cm and 40 cm: 40 cm + 40 cm = 80 cm
• Therefore, 4 dm + 40 cm = 80 cm

4. 1 m - 78 cm:

• Subtract 78 cm from 100 cm: 100 cm - 78 cm = 22 cm
• Therefore, 1 m - 78 cm = 22 cm

5. 90 dm - 70 dm:

• Subtract 70 dm from 90 dm: 90 dm - 70 dm = 20 dm
• Convert 20 dm to cm: 20 dm x 10 cm/dm = 200 cm
• Therefore, 90 dm - 70 dm = 200 cm