23.45%
Booya, grandma! Booya!

0%

She's not stupid enough to eat nothing but chocolate for a whole day, espacially if she's on an anorexic diet of 1000 (!?!?!??!) cal/day

2,145%.
25/30 * 24/29 * 23/28 * ... * 9/14

Heh, got both formula and calculation wrong!
It's actually

1,4%
25/30 * 24/29 * 23/28 * ... * 10/15

I agree with Machiavelli. Only other answer would be 100% - assuming she is having a bad day and binges on chocolate and remembers not to eat the rum ones because she avoids the liquor-flavored ones.

it isnt a trick question

I'd +1 JP's response but that would screw up his math

Just to clarify the question for my own personal peace of mind... Is Thelma a twisted bitch that is so jealous of her friend's new, slim look that she is tempting her with chocolates to ruin her diet, or is it the case that Thelma has no intention of offering any chocolates but Ely has sniffed them out and plans on stealing them, thus making her the bitch?

+1 Octavious.

30 indistinguishable, 80% of her cals is 800/1000 cals - @ 50 cal per chocolate that gives us (800 / 50) indistinguishable chocolate nuggets = 16 indistinguishable chocolate nuggets

The probability she will not eat any = 1 - probability she will eat some liquor
= 1 - ( (30/30)*5/30 + (30/30*25/30)*5/29 + (30/30*25/30*24/29)*5/28 + (30/30*25/30*24/29*23/28)*5/27 + (30/30*25/30*24/29*23/28*22/27)*5/26 + (30/30*25/30*24/29*23/28*22/27*21/26)*5/25 + (30/30*25/30*24/29*23/28*22/27*21/26 *20/25)*5/25... )

(5 / 30) + (((25 / 30) * 5) / 29) + (((((25 / 30) * 24) / 29) * 5) / 28) + (((((((25 / 30) * 24) / 29) * 23) / 28) * 5) / 27) + (((((((((25 / 30) * 24) / 29) * 23) / 28) * 22) / 27) * 5) / 26) + (((((((((((25 / 30) * 24) / 29) * 23) / 28) * 22) / 27) * 21) / 26) * 5) / 25) + (((((((((((20 / 30) * 24) / 29) * 23) / 28) * 22) / 27) * 21) / 26) * 5) / 25) + (((((((((((20 / 30) * 19) / 29) * 23) / 28) * 22) / 27) * 21) / 26) * 5) / 24) + (((((((((((20 / 30) * 19) / 29) * 18) / 28) * 22) / 27) * 21) / 26) * 5) / 23) + (((((((((((20 / 30) * 19) / 29) * 18) / 28) * 17) / 27) * 21) / 26) * 5) / 22) + (((((((((((20 / 30) * 19) / 29) * 18) / 28) * 17) / 27) * 16) / 26) * 5) / 21) + (((((((((((15 / 30) * 19) / 29) * 18) / 28) * 17) / 27) * 16) / 26) * 5) / 20) + (((((((((((15 / 30) * 14) / 29) * 18) / 28) * 17) / 27) * 16) / 26) * 5) / 19) + (((((((((((15 / 30) * 14) / 29) * 13) / 28) * 17) / 27) * 16) / 26) * 5) / 18) + (((((((((((15 / 30) * 14) / 29) * 13) / 28) * 12) / 27) * 16) / 26) * 5) / 17) + (((((((((((15 / 30) * 14) / 29) * 13) / 28) * 12) / 27) * 11) / 26) * 5) / 16) + (((((((((((10 / 30) * 14) / 29) * 13) / 28) * 12) / 27) * 11) / 26) * 5) / 15) + (((((((((((10 / 30) * 9) / 29) * 13) / 28) * 12) / 27) * 11) / 26) * 5) / 14) = 0.980904225

1 - 0.98... = 1.90957746%

(5/30 + (25/30)*5/29 + (25/30*24/29)*5/28 + (25/30*24/29*23/28)*5/27 + (25/30*24/29*23/28*22/27)*5/26 + (25/30*24/29*23/28*22/27*21/26)*5/25 + (20/30*24/29*23/28*22/27*21/26)*5/25 + (20/30*19/29*23/28*22/27*21/26)*5/24 + (20/30*19/29*18/28*22/27*21/26)*5/23 + (20/30*19/29*18/28*17/27*21/26)*5/22 + (20/30*19/29*18/28*17/27*16/26)*5/21 + (15/30*19/29*18/28*17/27*16/26)*5/20 + (15/30*14/29*18/28*17/27*16/26)*5/19 + (15/30*14/29*13/28*17/27*16/26)*5/18 + (15/30*14/29*13/28*12/27*16/26)*5/17 + (15/30*14/29*13/28*12/27*11/26)*5/16 + (10/30*14/29*13/28*12/27*11/26)*5/15 + (10/30*9/29*13/28*12/27*11/26)*5/14, even

That was exactly what I had but i chose not to ruin the surprise.

80%=800 calories
800 is 16 sweets
chances of not eating rum sweet for 16 turns are: 25/30 X 24/29 X 23/28 X 22/27 X 21/26 X 20/25 X 19/24 X 18/23 X 17/22 X 16/21 X 15/20 X 14/19 X 13/18 X 12/17 X 11/16 X 10/15 = 1,40%

I'm not sure how to read this. If the question asks what the probability is of her eating 80% of her daily allowance without getting a rum flavored chocolate -period- the answer is 1.4% as given above. If the question asks what the probability is that she consumes 80% of her allowance (16 chocolates) followed by her 17th chocolate being a rum one the answer is 1,4% * (5/14) = roughly 0.5%

Above answers seem close enough but to get a truly accurate figure I would need to know how quickly she eats

There is a 0% chance since she being so fat will just eat the whole box in one gulp! :-)

The question isn't specific enough. Does she eat other calories that day? If so, how many calories she consumes will depend on what time her friend gets there, and how many calories she has eaten before the chocolates arrive. Sheesh.

sorry, i think i got her to eat too many chocolates... leaving out the last term, my answer differs by even more.

i get 2.23% - what am i doing wrong??

it is 1.4% you can use a manual multiplication or a hypergeometric.

you guys these questions are tricks in any way.

next one? im thinking poisson for it

2. Photocards-R’-Us is a photo card printer. For this year, they have found that 10% of the cards they make are of inferior quality (blurred picture, faded colors, etc.) To attract customers to have their holiday cards printed with them, they are offering a 50% discount to customers who order a box of 50 cards if 10 of the cards in the box are of inferior quality. Manny is going to order a box of 50 Christmas photo cards at Photocards-R’-Us. What is the probability that he will receive a 50% discount on his holiday cards?

100% because he is unlucky. :-)

25%. I'm too lazy to work it out, so I just picked the first number that jumped out at me. :-)

Hmmm... I mostly take issue with the assumption that mathematical capacities are a sufficient proof of being "smart". I would actually argue that it's not even a necessary condition.

nor would i i just need help with these..... badly.

What Cachimbo said. If the smartest guy ever had never taken any courses in probability he would find it much more challenging then an average joe who had.

This question really depends on whether the 10% refers to the bulk production or individual packages of pictures. 10% of 50 is 5, so realistically you would never get 10, 20% of 50. But if there were two people each getting packages of 50, and if 10% (assuming it refers to the more bulk production) of the pictures were of inferior quality, then one of the people could get 10 pictures of inferior quality.

Then again, how smart can he be if he elected never to learn basic math?

Furthermore, what does "smart" really mean? Having knowledge? Having superior capability of learning? Actually using to use said capability of learning? These don't necessarily apply to academic learning.

Why not just read the picture guide sheet to which chocolates are which, and have all but the rum flavored ones. :) I know, I'm probably just being a smartass.