Further Applications

Question

Your friend has 19 different magazines and 5 different DVDs he is willing to loan you. Compute the following:


1. If you take one magazine and one DVD, how many different possibilities could you end up with?



2. If you take 5 magazines, how many collections of magazines are possible?



3. If you take 4 magazines and you are particular about what order you read them in, how many possibilities are there?



4. If you take 3 magazines and 3 DVDs, how many different possibilities could you end up with?

Answer 1

1. 19*5=95

2. 19!/5!(19-5)!

    19!/5!(14)!

    (19*18*17*16*15)/(5*4*3*2)

    11,628

3. 19*18*17*16=93,024

4. 19!/3!(19-3)!=19!/3!(16)!=(19*18*17)/(3*2)=969

    5!/3!(5-3)!=5!/3!(2)!=(5*4)/2=10

    10*969=9690