Converting Units of Weight (Grade 4)
Weight (mass) is measured in grams (g) and kilograms (kg). Small items like pencils are measured in grams, while heavier items like rice bags are measured in kilograms.
In Class 4, you will learn to convert between grams and kilograms, and solve word problems involving weight.
What is Converting Units of Weight - Class 4 Maths (Measurement)?
Weight (or mass) measures how heavy an object is. The two main units are:
- Gram (g) — used for light objects (a chapati, a coin).
- Kilogram (kg) — used for heavier objects (a bag of rice, a person).
Converting Units of Weight (Grade 4) Formula
1 kg = 1,000 g
kg to g → multiply by 1,000.
g to kg → divide by 1,000.
| Conversion | Operation | Example |
|---|---|---|
| kg to g | × 1,000 | 3 kg = 3,000 g |
| g to kg | ÷ 1,000 | 2,500 g = 2 kg 500 g |
Solved Examples
Example 1: Example 1: kg to g
Problem: Convert 5 kg to grams.
Solution:
Step 1: 1 kg = 1,000 g
Step 2: 5 kg = 5 × 1,000 = 5,000 g
Answer: 5 kg = 5,000 g.
Example 2: Example 2: g to kg and g
Problem: Convert 3,750 g to kg and g.
Solution:
Step 1: 3,750 ÷ 1,000 = 3 remainder 750.
Step 2: 3,750 g = 3 kg 750 g.
Answer: 3 kg 750 g.
Example 3: Example 3: Mixed kg and g to g
Problem: Convert 2 kg 400 g to grams.
Solution:
Step 1: 2 kg = 2,000 g
Step 2: 2,000 g + 400 g = 2,400 g
Answer: 2 kg 400 g = 2,400 g.
Example 4: Example 4: Adding weights
Problem: Ria buys 1 kg 300 g of apples and 2 kg 800 g of oranges. Find the total weight.
Solution:
Step 1: Add grams: 300 + 800 = 1,100 g = 1 kg 100 g.
Step 2: Add kg: 1 + 2 + 1 = 4 kg.
Step 3: Total = 4 kg 100 g.
Answer: Total weight = 4 kg 100 g.
Example 5: Example 5: Subtracting weights
Problem: A bag of sugar weighs 5 kg. Meera uses 1 kg 750 g. How much is left?
Solution:
Step 1: Convert: 5 kg = 5,000 g. 1 kg 750 g = 1,750 g.
Step 2: 5,000 − 1,750 = 3,250 g = 3 kg 250 g.
Answer: 3 kg 250 g of sugar is left.
Example 6: Example 6: Comparing weights
Problem: Which is heavier: 4 kg 200 g or 4,150 g?
Solution:
Step 1: Convert 4 kg 200 g to g: 4,000 + 200 = 4,200 g.
Step 2: Compare: 4,200 g vs 4,150 g. 4,200 > 4,150.
Answer: 4 kg 200 g is heavier.
Example 7: Example 7: Weight of packets
Problem: A packet of biscuits weighs 250 g. How many packets make 1 kg?
Solution:
Step 1: 1 kg = 1,000 g
Step 2: Number of packets = 1,000 ÷ 250 = 4
Answer: 4 packets make 1 kg.
Example 8: Example 8: Multiplying weights
Problem: One mango weighs 200 g. Arjun buys 8 mangoes. What is the total weight in kg and g?
Solution:
Step 1: Total = 200 × 8 = 1,600 g
Step 2: 1,600 g = 1 kg 600 g
Answer: Total weight = 1 kg 600 g.
Example 9: Example 9: Word problem
Problem: Dev's school bag weighs 3 kg 500 g. His tiffin box weighs 750 g and his water bottle weighs 500 g. What is the total weight he carries?
Solution:
Step 1: Convert all to g: 3,500 + 750 + 500 = 4,750 g
Step 2: 4,750 g = 4 kg 750 g
Answer: Dev carries 4 kg 750 g.
Key Points to Remember
- 1 kg = 1,000 g.
- To convert kg to g → multiply by 1,000.
- To convert g to kg → divide by 1,000.
- To add or subtract weights in different units, convert to the same unit first.
- Use g for light objects (biscuits, spices) and kg for heavy objects (rice, fruits, books).
- Half kg = 500 g. Quarter kg = 250 g.
Practice Problems
- Convert 8 kg to grams.
- Convert 6,300 g to kg and g.
- Add: 3 kg 600 g + 2 kg 800 g.
- Subtract: 10 kg − 4 kg 250 g.
- Which is heavier: 2 kg 500 g or 2,450 g?
- A box of sweets weighs 500 g. How many boxes make 3 kg?
- Priya buys 3 bags of flour, each weighing 1 kg 250 g. Find the total weight.
Frequently Asked Questions
Q1. How many grams are in 1 kilogram?
1 kilogram = 1,000 grams.
Q2. How do you convert kg to g?
Multiply by 1,000. For example, 4 kg = 4 × 1,000 = 4,000 g.
Q3. How do you convert g to kg?
Divide by 1,000. For example, 3,500 g = 3,500 ÷ 1,000 = 3 kg 500 g.
Q4. What is half a kilogram in grams?
Half a kilogram = 500 g. This is common in markets — 'aadha kilo' means 500 g.
Q5. What weighs about 1 gram?
A small paper clip or a one-rupee coin weighs about 1 gram.
Q6. What weighs about 1 kilogram?
A packet of sugar (standard size), a litre of water, or about 4 medium-sized apples weigh approximately 1 kg.
Q7. How do you add weights in kg and g?
Add the grams first. If the sum exceeds 1,000 g, convert to kg. Then add the kg. Example: 2 kg 600 g + 1 kg 700 g = 3 kg 1,300 g = 4 kg 300 g.
Q8. What is the difference between weight and mass?
In everyday language, weight and mass are used interchangeably. Technically, mass is the amount of matter (in kg/g) and weight is the force of gravity on it. In Class 4 maths, both terms mean the same thing.
Related Topics
- Measuring Weight in kg and g
- Converting Units of Length (Grade 4)
- Perimeter (Grade 4)
- Introduction to Area
- Area of Rectangle (Grade 4)
- Area of Square (Grade 4)
- Area and Perimeter Word Problems (Grade 4)
- Converting Units of Capacity (Grade 4)
- Area by Counting Squares
- Perimeter of Irregular Shapes
- Relationship Between Area and Perimeter
