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E:\Working\Brother_Education\Preparatory_Stage_Maths-4_(31-10-2023)\Open_Files\Chap-10
\\January 8, 2024 10:16 AM Bharat Arora P-1 Reader _________________________ Date: ___________________74

1. Choose the best estimate.

(a) The distance from your seat to the teacher’s table. 50 cm, 5 m, 15 mm

(b) The length of your pencil. 10 m, 10 cm, 10 mm

(c) The weight of your school bag. 400 g, 4 kg, 40 mg

(d) The diameter of a `2 coin. 25 mm, 25 cm, 25 m
(e) The capacity of your water bottle. 250 mL, 1 L, 500 L

(f) The capacity of a bucket. 20 mL, 200 L, 20 L
(g) The weight of a soap bar. 100 g, 1 kg, 100 kg

2. Which one is heavier: a basketball or a pumpkin of same size? Justify your answer.

3. How much water do you need to brush your teeth? Write your answer in millilitres.
4. How long do you ride your cycle or walk in the morning on a holiday?

Metric SySteM

In the previous classes, we have learnt about the units for measuring length, weight
(mass) and capacity. Metre (m), gram (g) and litre (L) are the base (standard) units

of weight (mass) and capacity, respectively.

Now, we shall learn some derived units for measuring these quantities.

These units are derived by multiplying and dividing the base (standard) units. Prefixes
such as kilo-, hecto-, deca-, deci-, centi- and milli- are used alongwith the base unit
to represent the derived units. That is,
Remember
kilometre, hectometre, decametre, ..., millimetre Each unit is 10 times the unit of its

kilogram, hectogram, decagram, ..., milligram right and one-tenth   1  of the

kilolitre, hectolitre, ..., centilitre, millilitre unit on its left.  10 

Look at the prefixes with their values as given below.
Smaller units
×10 ×10 ×10 ×10 ×10 ×10

km/kg/kL hm/hg/hL dam/dag/daL m/g/L dm/dg/dL cm/cg/cL mm/mg/mL

÷10 ÷10 ÷10 ÷10 ÷10 ÷10
Bigger units Base units

This is known as metric system of measurement. To change one metric unit of

measure to another, we multiply or divide by 10 for each step.

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