Measurements
Look at the below picture. Can you answer the below questions?
Who is heavier?
Who drinks more water?
The
- Measurement of Length
- Converting Metres and Centimitres
- Adding and Subtracting Lengths
- Measurement of Mass (Weight)
- Adding and Subtracting Weights
- Measurement of Capacity
- Adding and Subtracting Capacity
Measurement of Length
The
Centimetre
Centimetre is used to measure short lengths such as length of a pencil, length of a comb etc.
The short form of centimetre is
We can measure short lengths using a
Yes it is approaximately
Centimetre
Metre is used to measure long lengths like length of a football ground, length of a truck etc.
We measure long lengths using a
Very large distances are measured in
Height of a tree |
Length of a shoe. |
Height of a building |
Distance between two cities |
Length of a bus |
Height of a tree | metre |
Length of a shoe. | centimetre |
Height of a building | metre |
Distance between two cities | kilometre |
Length of a bus | metre |
Converting Metres and Centimitres
(i) Converting Metres into Centimitres
We know,
3 m = 3 x 100 = 300 cm.
5 m = 5 x 100 = 500 cm.
6 m 25 cm = (3 x 100) + 25 cm = (300 + 25) cm = 325 cm.
(ii) Converting Centimitres into Metres
We know,
Length in centimetre | Length in metre |
---|---|
200 cm | 2 m |
250 cm | 2 m 50 cm |
205 cm | 2 m 5 cm |
500 cm | 5 m |
120 cm | 1 m 20 cm |
Adding and Subtracting Lengths
Janet got two gift boxes on her birthday. One box is of height
Janet wants to see what will be the total height if she puts one box on top of another.
So new height = 50 cm + 35 cm.
(50 + 35) cm = 85 cm.
Add Lengths | Sum |
---|---|
60 cm + 30 cm | (60 + 30) cm = 90 cm |
70 cm + 40 cm | (70 + 40) cm = 110 cm = 1 m 10 cm |
2m 20 cm + 1 m | (2 + 1) m 20 cm = 3 m 20 cm |
3 m 40 cm + 3 m 30 cm | (3 + 3) m (40 + 30) cm = 6 m 70 cm |
2 m 60 cm + 5 m 70 cm | (2 + 5) m (60 + 70) cm = 7 m 130 cm = 7 m + 1 m 30 cm = 8 m 30 cm |
70 cm - 20 cm = (70 - 20) cm = 50 cm
5 m - 3 m = (5 - 3) m = 2 m
3 m 40 cm - 3 m 30 cm = 340 cm - 330 cm = 10 cm
5 m 20 cm - 1 m 90 cm = 520 cm - 190 cm = (520 - 190) cm = 330 cm = 3 m 30 cm
Subtract Lengths | Difference |
---|---|
60 cm + 10 cm | (60 - 10) cm = 50 cm |
1 m 50 cm - 50 cm | 150 cm - 50 cm = 100 cm = 1m |
2 m 40 cm - 1 m 90 cm | 240 cm - 190 cm = 50 cm |
10 m 50 cm - 7 m 95 cm | 1050 cm 795 cm = 255 cm = 2 m 55 cm |
Measurement of Mass (Weight)
Gram is written as
Gram is used to measure the weight of small or light weight objects.
kilogram is used to measure the weight of heavy things.
Kilogram is written as
A key weights about 20 g. |
A packet of rice having 25 kg of weight. |
A school bag having 2 kg of weight. |
A football having 250 gm of weight. |
A car is having around 1850kg of weight. |
To convert the weight in gram to kilogram, just divide the weight in gram by 1000. To divide a number by 1000, just remove the three digits at the right of the number. The remaining will be the weight in kilogram. The removed numbers will form the remaining weight in grams.
Adding and Subtracting Weights
Ryan is in the super market to buy some fruits. He collected
Can you help Ryan in getting the total weight?
Weight of apple = 5 kg
Weight of orange = 2 kg and 500 grams
Total Weight = 5 kg + 2 kg and 500 grams
= (5 + 2) kg and 500 grams
= 7 kg and 500 grams
Add Weights | Sum |
---|---|
40 g + 30 g | (40 + 30) g = 70 g |
80 g + 70 g | (80 + 70) g = 150 g |
750 g + 500 g | (750 + 500) g = 1250 g = 1 kg 250 g |
2 kg + 500 g | = 2kg 500 g |
3 kg 500 g + 1 kg 200 g | = 3500 g + 1200 g = 4700 g =4 kg 700 g |
When the weights are in the same unit, subtracting weights is as simple as subtracting the numbers.
When the weights are in mixed units, first conver the weights into gram and then subtract
Subtraction Weights | Difference |
---|---|
500 g - 200 g | = (500 - 200) gm = 300 gm |
10 kg - 2 kg | = (10 - 2) kg = 8 kg |
5 kg 250 g - 2 kg 500 g | = 5250 g - 2500 g = 2750 g 2 kg 750 g |
Measurement of Capacity
The quantity of liduid a container can hold is called
The standard units to measure capacity are
Millilitre is used to measure small quanitites of liquids.
Millilitre is denoted by
Litre is used to measure large quanitites of liquids.
Millilitre is denoted by
A bottle can hold 10 mL of perfume. |
A cup can hold 200 mL of tea. |
A can can hold 5 L of oil. |
A bucket can hold 20 L of water |
To convert the quantity in Litre to millilitre, just divide the quantity in Litre by 1000. To divide a number by 1000, just remove the three digits at the right of the number. The remaining will be the quantity in Litre. The removed numbers will form the remaining quantity in millilitre.
Adding and Subtracting Capacity
To add quantities of same unit, it is as simple as adding the digits. If the sum is more than 1000 mL, represent the quantity in litres.
If the quantities are expressed in mixed units, first convert the quantities into millilitre and then add.
Add Capacities | Sum |
---|---|
5 mL + 20 mL | = (5 + 20) mL = 25 mL |
750 mL + 600 mL | = (750 + 600) mL = 1350 mL = 1 L 350 mL |
1 L 250 mL + 2 L 500 mL | = 1250 mL + 2500 mL = 3750 mL 3 L 750 mL |
5 L + 1 L 250 mL | = 5000 mL + 1250 mL = 6250 mL = 6 L 250 mL |
To subtract quantities of same unit, it is as simple as subtracting the digits. If the difference is more than 1000 mL, represent the quantity in litres.
If the quantities are expressed in mixed units, first convert the quantities into millilitre and then subtract.
Subtract Capacities | Difference |
---|---|
50 mL - 20 mL | = (50 - 20) mL = 35 mL |
750 mL - 600 mL | = (750 - 600) mL = 150 mL |
1 L - 500 mL | = 1000 mL - 500 mL = 500 mL |
5 L 250 mL - 2 L 750 mL | = 5250 mL - 2750 mL = 2500 mL = 2 L 500 mL |