# A patient weighs 14 kg and requires drug A at a dose of 5 mg/kg per day. What is the total daily dose for this patient?

Jan 22, 2017

$70 m g$

#### Explanation:

First off is the cancellation of dimensions

$14 k g \cdot 5 \frac{m g}{k g} = 14 \cancel{k g} \cdot 5 \frac{m g}{\cancel{k g}} = \left(14 \cdot 5\right) m g$

For simplicity you can split 14 up and distribute

=((10+4)*5)mg=((5(10)+5(4))mg=(50+20)mg

$= 70 m g$

Jan 22, 2017

$70 m g$

#### Explanation:

Use the units of measurement to guide as to how to do the calculation.

You need to end up with just $m g$

We are given $\textcolor{red}{K g} \mathmr{and} \textcolor{g r e e n}{\frac{m g}{K g}}$

If we do this: color(red)(Kg)color(green)(xx(mg)/(Kg) we end up with:

color(green)((color(red)(Kg))/(Kg)xxmg ->(cancel(color(red)(Kg)))/cancel((Kg))xxmg" "  as required

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Doing the same thing with the numbers:

14 color(white)(.)color(red)(Kg)xx5 color(white)(.) color(green)((mg)/(Kg)) = 70 mg
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A quick way of calculating $14 \times 5$ is to think of 5 as $\frac{10}{2}$

$10 \times 14 = 140 \mathmr{and} \frac{1}{2} \times 140 = 70$