# The mass of a moon rock is 3.5 kilograms. What is the mass of the moon rock in grams?

Nov 20, 2016

$3 , 500$ grams

#### Explanation:

$1 \text{ kilogram} = 1 , 000$g

If you use a smaller unit, your answer is bigger.
If you use a bigger unit, your answer is smaller.

To change from Kg to g you need to multiply by 1,000.

$1 \text{ kilogram} = 1 , 000$g

$3.5 k g = 3.5 \times 1000$

=$3 , 500$ grams

Nov 20, 2016

$3.5 \text{ kilogram "=" "3500" grams}$

#### Explanation:

$\textcolor{b l u e}{\text{Preamble}}$

When you have an equation the actual value to the left of = must be the same as the actual value to the right of =.

So if you change the left in some way you must also do something to the right so that the equation is still true. Otherwise it becomes false.

$2 = 2$ is true$\text{ } \to 2 + 5 = 2 + 5$ is also true
$2 = 1$ is false

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$\textcolor{b l u e}{\text{Answering the question}}$

Known:

$1 \text{ kilogram "=" "1000" grams}$

But we have 3.5 kilograms

Multiply both sides by 3.5

$3.5 \times 1 \text{ kilogram "=" "3.5xx1000" grams}$

$3.5 \text{ kilogram "=" "3500" grams}$