This is asking how many ways can we choose 13 songs from a set of 25.
The formula is:
n! / r! * (n -r)! =
25! / 13! * 12! which equals
25 *24 *23 *22 *21 *20 *19 *18 *17 *16 *15 *14 *13! divided by
13! * 12! which equals
25 *24 *23 *22 *21 *20 *19 *18 *17 *16 *15 *14 divided by
12* 11* 10* 9* 8* 7* 6* 5* 4* 3* 2*
which equals
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2,490,952,020,480,000
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divided by
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479,001,600
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and that equals
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5,200,300
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</span>
combinations
Here's a combination calculator to check your work:
http://www.1728.org/combinat.htm
Answer:
There are 100 milligrams of metoclopramide HCl in each milliliter of the prescription
Step-by-step explanation:
When the prescription says Purified water qs ad 100 mL means that if we were to make this, we should add the quantities given and then, fill it up with water until we have 100 mL of solution, being the key words qs ad, meaning sufficient quantity to get the amount of mixture given.
Then, knowing there is 10 grams of metoclopramide HCl per 100 mL of prescription, that means there is (1 gram = 1000 milligrams) 10000 milligrams of metoclopramide HCl per 100 mL of prescription. That is a concentration given in a mass/volume way.
Knowing the concentration, we can calculate it per mL instead of per 100 mL

The answer is (2,-6) look at the picture to see how to do it
You simply put 40 over a hundred and 55 over n (which is the number were trying to find) so you do cross multiplication. 55 times a hundred and after you get the answer. You divide it by 40 and should get 137.5.