Topic outline

    • Measuring Mass (or weight)

      Mass is a measure of how heavy something is. We use a balance scales or a weighing scales to measure mass (or weight)

      Mass is measured in grams (g) and kilograms (kg). We use grams to weigh lighter objects and kilograms to weigh heavier objects.

      1 kg = 1000g

      Or

      1000g = 1kg

      The standard unit of measurement of mass is Kilogram.

       

      Conversion of kg into g

      In order to convert kilograms into grams we multiply by 1000

      Example: Change 4 kg into grams.

      Since 1 kg =1000g

      4kg = 4 x 1000g

            = 4000g

      Note: In conversion of unit, we always multiply when we go from higher unit to lower unit; such as from kg to g.



      Addition

      Step1: Add the gram column

      Step2: Add the kg column

      Example 1:

      Add 75kg 582g and 13kg 410g


      Example 2:

      Add 94kg 215g and 6kg 757g


      Example 3:

      Ravi purchased 5kg 300g of a packet of rice and 4kg 200g of a packet of wheat flour. How much is the total weight of both the packets?

      Solution:

      Weight of rice = 5kg 300g

      Weight of wheat flour = 4kg 200g

      Total weight of both the packets = 5kg 300g + 4kg 200g




      Subtraction

      Step1: Subtract the gram column

      Step2: Subtract the kg column

      Example1:

      Subtract 13kg 410g from 75kg 582g


      Example2:

      Dev weighs 39kg 900g. Manit weighs 35kg 600g. Who weighs more and by how much?

      Solution:

      Dev’s weight = 39kg 900g

      Manit’s weight = 35kg 600g

      Dev weighs more by = 39kg 900g – 35kg 600g


       

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