In short, weight shows “how much something weighs” or “how heavy it is.”
Anu has recorded the weights of the items in her house. Check if she has recorded them correctly by putting a tick against them if they look correct.
Sol:
Explanation:
1. Iron Almirah
This is too light because iron almirahs are very heavy and usually weigh many kilograms.2. Bed
This is correct because beds are heavy, but we can still move them with the help of others.3. Rice Bag
This is correct because rice is often sold in 5 kg bags, which matches the weight.4. Sofa
This is too light because sofas are big and heavy, not just a few grams.5. Bucket
This is correct because a big bucket, especially when filled with water, can weigh this much.6. Water Bottle
This is correct because a full water bottle can weigh about 1 kilogram.7. Refrigerator
This is too light because refrigerators are very heavy and usually weigh many kilograms.
Read the scales. Write the correct weight in the space given below.
Sol:
Needle between 0 and 1 kg.
Each small line = 100 g.
Needle at 600 g.
Between 1 kg and 2 kg.
Needle at 1 kg 800 g.
Between 2 kg and 3 kg.
Exactly halfway → 2 kg 500 g.
Between 2 kg and 3 kg.
Needle at 2 kg 600 g.
Between 0 g and 250 g.
Needle at 150 g.
Between 500 g and 750 g.
Needle at 650 g.
Weight can be measured in kilograms (kg) and grams (g).
Match the bags that have the same weight. You can use the double number line given below.
Sol:
Step 1: Weighing Balance 1
It has weights in kilograms:
5 kg, 10 kg, 3 kg, 6 kg, 25 kg, 30 kg
Step 2: Convert them into grams
5 kg = 5 × 1000 = 5000 g
10 kg = 10 × 1000 = 10,000 g
3 kg = 3 × 1000 = 3000 g
6 kg = 6 × 1000 = 6000 g
25 kg = 25 × 1000 = 25,000 g
30 kg = 30 × 1000 = 30,000 g
Step 3: Match with Weighing Balance 2
5 kg ↔ 5000 g
10 kg ↔ 10,000 g
3 kg ↔ 3000 g
6 kg ↔ 6000 g
25 kg ↔ 25,000 g
30 kg ↔ 30,000 g
Step 4: Understanding the Double Number Line
Top line shows kilograms
Bottom line shows grams
To go from kilograms to grams, multiply by 1000
To go from grams to kilograms, divide by 1000
Examples from the number line:
1 kg = 1000 g
3 kg = 3000 g
8 kg = 8000 g
20 kg = 20,000 g
30 kg = 30,000 g
Shrenu is baking cakes for her shop. She needs 3 kg 500 g of flour. Her kitchen scale measures only in grams. What should her kitchen scale show for 3 kg 500 g of flour?
Sol:
What would be 2 kg 250 g of flour in grams?
Sol:
1. Harpreet's family planned a picnic over the weekend. Her mother and father packed different food items to take along. The following is the list of fruits they carried.
Among the fruits they carried, which one has the
(a) highest weight? __________
(b) least weight? __________
(c) Arrange the items in descending order of their weight.__________ __________ __________ __________
Sol:
(a) Highest weight?
Watermelon - 3 kg
(b) least weight?
Apples - 1 kg 250 g
(c) Arrange the items in descending order of their weight.
Watermelon, Mangoes, Pineapple, Apples
2. Compare the weights using <, =, > signs.
Sol:
If a sugar sachet weighs 5g, how much will it be in milligrams?
Sol: We know that 1 g = 1000 mg
Thus, 5 g = 5 x 1000 = 5000 mg
In a kingdom, the king donates wheat grains equal to 10 times his weight on his birthday.
(a) If he donates 800 kg of wheat grain this birthday, what is his current weight? _______ kg.
(b) If he had donated 780 kg of wheat grain on his last birthday, what was his weight last year? _______ kg.
(c) How much weight did he gain in a year until this birthday?_______ kg
Sol: (a) 80 kg
(b) 78 kg
(c) (80 - 78) kg = 2 kg
Always remember these weight conversions - they are the key to changing between milligrams, grams, kilograms, quintals, and tonnes!
Rathna went to the local grocery store and bought several items.
She bought 2 kg 500 g rice for daily use and 1 kg 750 g additional rice for the upcoming Pongal festival. How much total rice did she buy?
Sol: We have three different waysto add these weights:
- Mental Method (breaking into parts):
- Add kilograms and grams separately.
- 2 kg + 1 kg = 3 kg
- 500 g + 750 g = 1250 g = 1 kg 250 g
- So, 3 kg + 1 kg 250 g = 4 kg 250 g
- Column Method:
- Write kg and g in columns and add them.
- Carry over 1000 g as 1 kg.
- Answer is 4 kg 250 g.
- Convert to grams:
- 2 kg 500 g = 2500 g
- 1 kg 750 g = 1750 g
- Add: 2500 g + 1750 g = 4250 g
- Convert back: 4250 g = 4 kg 250 g
Weighing is not just about adding and subtracting — sometimes we need to multiply or divide weights.
Why it’s useful:
Always remember:
1. A farmer weighs a sack of potatoes and finds it to be 10 kg 500 g.If the farmer has 4 such potato sacks, what is the total weight of all the sacks?
Sol: 4 × 10 kg 500 g
= 4 ×10 kg and 4 × 500 g
= 40 kg + 2000 g
= 40 kg + 2 kg
= 42 kg.
2. A box of nuts weighing 4 kg 800 g is equally distributed into 4 smaller boxes. What is the weight of each small box in grams?
Sol: 4 kg ÷ 4 = 1 kg
800 g ÷ 4 = 200 g
So, 4 kg 800 g ÷ 4 = 1 kg 200 g
Write the total capacity of the following containers in each blank.
Sol: Observe the beakers:
- Big beaker = 1 litre (1 l = 1000 ml)
- Medium beaker = 500 ml
- Small beaker = 100 ml
Add the capacities in each set.
Top-left set: 1 l + 500 ml + 100 ml = 1 l 600 ml
Top-right set: 1 l + 500 ml = 1 l 500 ml
Bottom-left set: 100 ml + 100 ml + 500 ml = 700 ml (or 0 l 700 ml)
Bottom-right set: 1 l + 1 l + 100 ml = 2 l 100 ml
Khayal chacha delivers the following amounts of milk each week to different families.
Dev’s family needs 1 l milk every day. On Sunday, they need 500 ml more.Quantity of milk they need on Sunday = 1 l + 500 ml = 1,000 ml + 500 ml = 1,500 ml
Sol:
1. Bhalerao’s vessel mark for 2 litres
Rule: 1 l = 1000 ml
2 l = 2 × 1000 = 2000 ml
So the mark you will see is 2000 ml.
2. Fill the litres–millilitres blanks
(Use 1 l = 1000 ml)1 l → 1000 ml
2 l → 2000 ml
6 l → 6000 ml
8 l → 8000 ml
12 l → 12,000 ml
14 l → 14,000 ml
20 l → 20,000 ml
25 l → 25,000 mlSo the filled rows are:
3. Weekly delivery table (convert each using 1 l = 1000 ml)
4. Dev’s family
Needs 1 l every day, and on Sunday, 500 ml more.
1 l + 500 ml = 1000 ml + 500 ml = 1500 ml
Kiran owns a petrol pump. She records the details of the sales of petrol in a day.
(a) How much more fuel is bought for buses than for trucks?
(b) What is the total quantity of fuel filled from the petrol pump on that day?
Sol: First, find the total fuel for each vehicle type (No. of vehicles × fuel in each):
(a) How much more for buses than trucks?
Buses: 1,800 litres
Trucks: 1,500 litres
Difference: 1,800 − 1,500 = 300 litres more for buses.
(b) Total fuel filled that day
Add all the totals:
1,500 + 1,800 + 500 + 96 + 125 = 4,021 litres.
Sam and Tina fill petrol in their bikes. Tina bought 2 l 500 ml of petrol. Sam bought 2 l 800 ml more petrol than Tina. How much petrol didSam buy?
Sol: Sam found the quantity of petrol by adding like quantities.
2 l 500 ml + 2 l 800 ml
= 2 l + 2 l and 500 ml + 800 ml
= 4 l and 1,300 ml
= 4 l and 1 l and 300 ml
= 5 l 300 mlTina converted the quantities into ml, that is, 2,500 ml and 2,800 ml.
Total quantity of petrol bought by Sam = 2,500 ml + 2,800 ml = 5,300 ml =5 l 300 ml.
After refuelling, Sam found his fuel gauge reading 9 l.
How much fuel did his bike have before refuelling? The quantity of fuel Sam’s bike had before refuelling is–
Sam’s bike had 3l 700ml of fuel before refuelling.
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