Sunday, October 28, 2007

Am I annoying yet?

In a department store there are 120 customers, 90 of whom will buy at least one item. If 5 customers are selected at random, one by one, find the probability that all will buy at least one item.

Now I know that I must subtract the probability of the 90 from 1. but EH? why cant I do that?

the answer in the book is 243/1024 but it does not show how it got there.

yay math love!

16 comments:

Nathalie Thompson said...

Hi Suzie, Red Tin Heart told me to stop by (re: trick or treating?) I emailed you my address- does that still work for you? Or do you need something else (first born ;) ? Heehee Kidding.

I am fascinated by statistics, although they often confuse the heck out of me. Like who THINKS to calculate the miles per hours speed of a bee and WHY? According to the current Happy Meal box, promoting "The Bee Movie", a bee flies one mile per hour. I will remember that silly bit of trivia forever, but won't remember that my daughter wants her favorite sweat jacket washed for school tomorrow!

Bookviper said...

I feel your pain. I had a test in my statistics class last week. Walked out with a lackluster C. Best wishes that you do better than I.

Dave said...

ARRRRRRGGH! Math!

Anonymous said...

I wonder if there are
Math Tudorial's online
that could help with that.

Have a Blessed Week!

Flassie

Thanatos2424 said...
This comment has been removed by the author.
Anonymous said...

Sorry, no google/blogger account. Statistics s kicking my butt this semester too. I think this is how:
the probability of a person buying something= 90/120=3/4
so that probability the first person buys something times 3/4 again the probability the second person buys repeat as needed ie 5 times for 5 people so
(3/4)^5=243/1024
Does that make any sense/help at all? Feel free to email me FeMinchin@vassar.edu
Love and black cats
Felicia

Nina said...

ha, ha, ho, ho, hee, hee, hee, %^&*()(*&^%$%^&*()

changapeluda said...
This comment has been removed by the author.
babytreese said...

"My name is Theresa and I am math impaired." "Hello Theresa" ;-) Good luck baby girl...

suzi blu said...

Felicia is right oh THANK YOU THANK YOU THANK YOU!

ISA ^_^ said...

I am too bad in math, I hate math !!! I had 8/20 at my final exam ... LOL !!
Hugs
ISA ^_^

bh said...

90/120 = 3/4 = 75% chance that any one will buy something.

So for five people who each have a probability of 3/4 to buy something...

3/4 x 3/4 x 3/4 x 3/4 x 3/4=
243/1024

3x3x3x3x3=243
4x4x4x4x4=1024

bh
the music matters

Julie said...

Math makes my brain cry.

Melanie said...

Okay this is on a different subject all together but I finally got to use the water soluble oil pastels - I had tried before, but didn't work for me. So this time I gessoed my page and left it thick and course (I love texture!), dried then drew with my pastel. And smooshed - and boy do they SMOOSH! Thanks for telling me about them - now I have a page that looks like one from all the art journals I so admire!

Carolyn said...

Hey, I forgot all about statistics as soon as I passed. Sorry, can't help you there.. I just wanted to stop by your blog and let you know that you have really inspired me. I have been drawing/painting/sewing a whole lot more lately. After watching your vlogs, all anxiety leaves me. Its really nice to be reminded that life isn't a big deal, and actually it is very beautiful and you can do what you want with it.
So thanks again,
Carolyn

Artsy said...

I have trouble with numbers over 6. LOL