Do you know how much you weigh in kilograms? Would that be more or less than a domestic cat? How about a tiger? It's easier to estimate the weight of something when you compare it to something else.

You can also consider the weight of a similar but differently sized object if it would be made from the same material. So if I know one bag of flour weighs around $500$500 g, I can estimate that $10$10 bags of flour would weigh $5$5 kg.

Worked Examples

question 1

What is the most appropriate measure for the mass of a $dog$ ?

$0.1$0.1kg
A
$1$1kg
B
$10$10kg
C

question 2

The container shown has $10$10 $kg$ of $sand$ in it. Estimate the weight of the container when it is full.

$8$8 $kg$
A
$10$10 $kg$
B
$22$22 $kg$
C
$12$12 $kg$
D

question 3

The container shown has $4$4 $mg$ of $foam$ in it. Estimate the weight of the container when it is full.

Not to scale

$5$5 $mg$
A
$13$13 $mg$
B
$8$8 $mg$
C
$4$4 $mg$
D

Outcomes

5.M2.09

Select and justify the most appropriate standard unit to measure mass (i.e., milligram, gram, kilogram, tonne)

Estimate mass