Page 95 - Math Smart - 7

4.32 Ordering decimals with different

units of measurement

Sometimes it is helpful to compare two or more quantities such as travelling time, E
income, expenses, size, mass, speed, temperature, height and distance. It is easier
t RECALL
to compare and order decimals that have the same unit of measurement. For
£
example, it is difficult to compare a length in kilometres with a length in metres.
We need to change both quantities to have the same unit before comparing. uengin ivies
Conversion Operation
Example 8 mm m -r 1000

m —*■ mm X 1000
O Arrange the masses from heaviest to lightest.
cm ^ m ■rlOO
0.5 kg 560 g 1.25 kg 1020 g
m —cm X 100
m —> km ■r 1000
Convert all masses to the same unit. In this example,
1 we will convert kg to g. X 1000
1 ...
0.5 kg X 1000 = 500 g
Recall that 1000 g = 1 kg. Operation
1.25 kg X 1000 = 1250 g Conversion
g-^kg 1000
Order the masses from heaviest to lightest. kg-^g X 1000
^ 1250g 1020g 560g 500 g
Conversion Operation
Write down the masses in order from heaviest to lightest using the
m£^- £ ■r 1000
original units given.
ml X 1000
1.25 kg 1020 g 560 g 0.50 kg

O Write the distances in order from shortest to longest.

2.5 m 273 cm 2.05 m 256 cm
Convert the distances to the same unit. In this example, we will
convert cm to m.
273 cm 100 = 2.73 m

256 cm 100 = 2.56 m
Check My
Order the lengths from shortest to longest.
Understanding
2.05 m 2.5 m 2.56 m 2.73 m
Convert these measurements,
Write down the lengths in order from shortest to longest using the
original units given. a) 28.5 cm = m

2.05 m 2.5 m 256 cm 273 cm
b) 1.706 m = cm

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