Question

Question #410ad

Answer 1

Here's what I got.

Explanation:

You can start by calculating the total number of grams of this drug that the patient needs in `1` day.

Since you know that the dosage is set at `"1.9 g"` every `"6 h"`, you can say that the patient will need

`"1.9 g/6 h" = "1.9 g"/(6color(red)(cancel(color(black)("hours")))) * (24color(red)(cancel(color(black)("hours"))))/"1 day" = "7.6 g"/"1 day" = "7.6 g/day"`

Next, use the fact that

`color(blue)(ul(color(black)("1 g" = 10^3color(white)(.)"mg")))`

to convert the sample to milligrams

`7.6 color(red)(cancel(color(black)("g"))) * (10^3color(white)(.)"mg")/(1color(red)(cancel(color(black)("g")))) = 7.6 * 10^3color(white)(.)"mg"`

So, you know that your patient needs `7.6 * 10^3` `"mg"` of this drug per day. To find the number of tablets needed to deliver this sample to the patient, use the fact that `1` tablet has a mass of `"500 mg"`.

`7.6 * 10^3 color(red)(cancel(color(black)("mg"))) * "1 tablet"/(500color(red)(cancel(color(black)("g")))) = "15.2 tablets"`

Now, if you cannot split a table into `5` equal parts so that you can give

`15.2 = 15 1/5`

tablets to the patient--which would be consistent with the fact that the answer must have `1` significant figure--then my guess is that `"1.9 g"` is a typo and that the actual value is `"1.0 g"`.

In this case, you have

`"1.0 g/6 h = 4 g/day"`

which means that you will need

`4 * 10^3 color(red)(cancel(color(black)("mg"))) * "1 tablet"/(500color(red)(cancel(color(black)("mg")))) = "8 tablets"`

Since the values given to you justify a `1`-sig-fig answer, this is most likely what the problem looked like.