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## #1 Help Me ! » A line is neither concave up nor concave down. what is that line » 2018-08-03 20:50:46

Hannibal lecter
Replies: 2

A line is neither concave up nor concave down.

what is that line, can I see a picture for it
I know the meaning of concave up and concave down.
but not others

## #2 Re: Help Me ! » fair coin probablity » 2018-06-06 14:34:08

thank you, that's amazing
but  I have another question please,

Q) two dice are thrown  if their  sum is less than 8 , what is the probability that one of them is 4?

## #3 Help Me ! » fair coin probablity » 2018-06-06 06:22:23

Hannibal lecter
Replies: 3

a fair coin is tossed 40 times, find the probability of getting 10 Heads!

## #4 Re: Help Me ! » a question of a dice in probabilty » 2018-04-14 11:37:30

you two were be able to give me the value of the denominator before the exam is finish,
but you didn't help me,

are you always answer the questions in this way ?

## #5 Re: Help Me ! » a question of a dice in probabilty » 2018-04-01 11:40:14

you are too late, my answer in the exam was p = 2 / (36-4)

## #6 Help Me ! » please help me with that question as you can 9:05 bob bundy » 2018-03-31 11:27:05

Hannibal lecter
Replies: 1

Five balls (2 red , 1 blue , 1 green , 1 yellow )
are arranged in a circle, Find the probability that the red balls are not together

## #7 Re: Help Me ! » very real important question about probability .. » 2018-03-31 07:51:51

is n = 3 or r = 3 ? if the coin tossed 3 times , or it's not either

## #8 Re: Help Me ! » a question of a dice in probabilty » 2018-03-31 06:50:44

are you there bob bundy, can you tell what is the denominator  value please is it 36 or not

## #9 Re: Help Me ! » very real important question about probability .. » 2018-03-31 02:52:01

I'll see that after few hours, but

do the formula you provide mean like that following picture,
( please look at it, is is the same as you wrote)

## #10 Re: Help Me ! » very real important question about probability .. » 2018-03-30 23:51:32

nCr x (1/2)power r x (1/2) power(n-r)

can you write down this rule again more clearly please,
I can't not understand what is x (1/2)power r please.. my exam is tomorrow
is x a variable or multiplication symbol,
please I won't ask too much again, but the formula is not clear can you type it clearly or like image or anything...
and what will be n value and the k value ?

## #11 Re: Help Me ! » a question of a dice in probabilty » 2018-03-30 23:45:50

then what is the denominator ?

## #12 Re: Help Me ! » very real important question about probability .. » 2018-03-30 11:02:38

this is the full question in the following image :
and please give me the full answer for all the questions a b and c, because I have an exam please! just this time

## #13 Re: Help Me ! » very real important question about probability .. » 2018-03-30 10:59:39

yes but He is asking for a general rule!
is there a general rule for that?

## #14 Re: Help Me ! » a question of a dice in probabilty » 2018-03-30 10:56:45

there is 2,

do you mean the solution is 2/36??????????? really just that?

## #15 Help Me ! » very real important question about probability .. » 2018-03-29 13:12:24

Hannibal lecter
Replies: 10

when you toss a coin three times, Let x denote the number of heads that appear
find p(x)?

!!!!

is there a general law for this question? how to find this probability?
it's really harddddddddd

## #16 Help Me ! » a question of a dice in probabilty » 2018-03-29 12:35:18

Hannibal lecter
Replies: 9

Hi, two dice are thrown, fine the probability that the sum is 8 if you know one of them is 5

## #17 Re: Help Me ! » relationship between Probability and (Combinations and Permutations) » 2018-03-12 20:40:05

How did you calculate this combinations  by its rule?

or you just know everything about the dice
please tell me how did you calculate this using the rule of combinations (n!/r!(n − r)!)

## #18 Re: Help Me ! » relationship between Probability and (Combinations and Permutations) » 2018-03-09 22:53:45

2 (P= 1/6) the second a 4 (P=1/6) and the third a 1 (P=1/6), is the number gender is the 6 possibilities or the 6 digit of the die?

we didn't use the combinations , you just solve the question before calculating the combinations,

and now if we  allowed to re-arrange them and we know that there is six possibilities what after?

## #19 Re: Help Me ! » why I can't calculate the probability of birthday problem without... » 2018-03-09 12:52:59

how to start calculating

## #20 Help Me ! » how many permutation the following set has » 2018-03-09 07:21:39

Hannibal lecter
Replies: 1

Hi, how many permutation the set has X= ={1,1,2,2,6}

int  repetitions and without  repetitions

## #21 Re: Help Me ! » important question about Probability » 2018-03-09 06:41:02

and that the solution of the teacher note that the last number I think not 0.3996 it's 0.1721

anyway please see his solution :-

## #22 Re: Help Me ! » important question about Probability » 2018-03-09 06:05:28

from where did you get the number  4 / 14 ???
and why didn't you use Combinations Or  Permutations rules?
I'm so confused I can't imagine this

how could you  avoid repetitions by just divide by 2 or 6!!! isn't there something called combinations  without repetition or Permutations  without repetition

## #23 Re: Help Me ! » why I can't calculate the probability of birthday problem without... » 2018-03-09 05:41:09

I can't imagine how could it involve too many calculation? can you give me  a hint

## #24 Help Me ! » why I can't calculate the probability of birthday problem without... » 2018-03-09 02:31:12

Hannibal lecter
Replies: 4

Hi, why I can't calculate the probability of birthday problem without taking the complement ?

for example why I can't calculate the probability of at least 2 shared birthday in a room of 30 people
without taking the complement ?

is it too hard? but how to do it?

## #25 Re: Help Me ! » relationship between Probability and (Combinations and Permutations) » 2018-03-09 00:06:24

can you give me another easy example please, I didn't understand that one, maybe an example of marbles or dice or coins, ..
please just give me an easy example,

and what did you mean when you said 5 of 11 ? is it mean p(n=5,k=11) or vice versa?
and did you use the rule of Permutations with Repetition or without ?

as well as ..

the rule of probability is = Number of ways it can happen (event) /Total number of outcomes( sample space)

is the (Combinations and Permutations) the same as =Total number of outcomes( sample space)? or what..