username: fumblingperch
You pick a wooden box at random and draws out a Bitcoin. What is the probability that the second coin is also a Bitcoin?
You get 50%
How did you arrive at the solution?
because in moment you have pick 1 Bitcoin already, only can be box 1 or 3
What is this classic problem called?
don't know
Topic: [ROLLIN.IO] Rollin 2016 New Year // Contests & Giveaways!! / CLOSED. - page 21. (Read 24817 times)
December 11, 2015, 12:56:31 PM
December 11, 2015, 12:52:07 PM
I think its 50/50 change ?
Cause if you picked one bitcoin there is only 2 boxes that contains one for more btc's
Cause if you picked one bitcoin there is only 2 boxes that contains one for more btc's
December 11, 2015, 12:47:18 PM
The probability is 2/3....in fact the thing that you pick a BTC coin don't change probability of the choose of the box.
If for example we have:
Box 1: BTC 1 -btc2
Box 2: ltc 1 -ltc 2
Box 3: BTC 3 - ltc 3
The extracted BTC could be only one of BTC 1, btc 2, BTC 3, so possible cases for the BTC are 3/3.
If I pick one of 3, the P is now 2/3.
If for example we have:
Box 1: BTC 1 -btc2
Box 2: ltc 1 -ltc 2
Box 3: BTC 3 - ltc 3
The extracted BTC could be only one of BTC 1, btc 2, BTC 3, so possible cases for the BTC are 3/3.
If I pick one of 3, the P is now 2/3.
December 11, 2015, 12:42:04 PM
You might be correct (or wrong). But I won't say it till I get 2 more attempts. 
December 11, 2015, 12:35:34 PM
7. At the Rollin game show, you are given three wooden boxes:
one containing two Bitcoins, another box containing two Litecoins, and one containing a Bitcoin and a Litecoin. (assume all are physical ones)
You pick a wooden box at random and draws out a Bitcoin. What is the probability that the second coin is also a Bitcoin? (2 mBTC) How did you arrive at the solution? (4 mBTC) What is this classic problem called? (1 mBTC)
I'm going to go with my math-gut-feeling one containing two Bitcoins, another box containing two Litecoins, and one containing a Bitcoin and a Litecoin. (assume all are physical ones)
You pick a wooden box at random and draws out a Bitcoin. What is the probability that the second coin is also a Bitcoin? (2 mBTC) How did you arrive at the solution? (4 mBTC) What is this classic problem called? (1 mBTC)
The probability is 66.667%
You know for sure you don't have the box with 2 litecoins.
That leaves two options:
1. you have the box with 2 bitcoins
2. you have the box with 1 bitcoin and 1 litecoin
Before getting a coin out of these 2 boxes, there is a 75% chance to get a bitcoin, and 25% chance to get a litecoin. You got a bitcoin already, which makes it more likely you have the bitcoin-box than the bitcoin/litecoin-box.
I have no idea what this classic bitcoin and litecoin problem is called
Username Loyce
December 11, 2015, 12:19:36 PM
On-thread Trivia!
aaand the question for today is:
7. At the Rollin game show, you are given three wooden boxes:
one containing two Bitcoins, another box containing two Litecoins, and one containing a Bitcoin and a Litecoin. (assume all are physical ones)
You pick a wooden box at random and draws out a Bitcoin. What is the probability that the second coin is also a Bitcoin? (2 mBTC) How did you arrive at the solution? (4 mBTC) What is this classic problem called? (1 mBTC)
Post your answer(s) with your Rollin account. Rollin account should be at least level 2 OR the bitcointalk account full member and above. First to answer correctly, to the point wins the prize.
Remember, no edits.
aaand the question for today is:
7. At the Rollin game show, you are given three wooden boxes:
one containing two Bitcoins, another box containing two Litecoins, and one containing a Bitcoin and a Litecoin. (assume all are physical ones)
You pick a wooden box at random and draws out a Bitcoin. What is the probability that the second coin is also a Bitcoin? (2 mBTC) How did you arrive at the solution? (4 mBTC) What is this classic problem called? (1 mBTC)
Post your answer(s) with your Rollin account. Rollin account should be at least level 2 OR the bitcointalk account full member and above. First to answer correctly, to the point wins the prize.
Remember, no edits.
December 11, 2015, 02:54:21 AM
Username :Visions
Code : XMAS
Code : XMAS
December 11, 2015, 02:51:56 AM
code r8
prediction: 1,998,999,888
user:aRp
prediction: 1,998,999,888
user:aRp
December 11, 2015, 01:07:18 AM
Username: pokerowned
Code: XMAS
Thx rollin for holding these contests n giveaways. The community appreciates the shot at free money
Code: XMAS
Thx rollin for holding these contests n giveaways. The community appreciates the shot at free money
December 11, 2015, 12:44:43 AM
Reminder: we have the prediction contest still running.
Just 9 players so far.
Example entry :
Just 9 players so far.
Example entry :
Predict the rolls contest. Code : R8
My prediction: 1.867.780.540
Good luck all
My prediction: 1.867.780.540
Good luck all
December 10, 2015, 06:48:57 AM
code r8
prediction: 1,999,934,645
user: CASIO
prediction: 1,999,934,645
user: CASIO
December 10, 2015, 02:13:18 AM
predict roll contest : code r8
my prediction : 2.000.000.000
my prediction : 2.000.000.000
December 10, 2015, 01:25:46 AM
Username : Coino
Code : XMAS
Code : XMAS
Username: gwapo
code: xmas
code: xmas
username quincy51
xmas times to all my friends at rollin
xmas times to all my friends at rollin
Entered. Good luck.
December 10, 2015, 01:22:18 AM
username quincy51
xmas times to all my friends at rollin
xmas times to all my friends at rollin
December 10, 2015, 01:21:52 AM
Username: gwapo
code: xmas
code: xmas
December 10, 2015, 01:18:26 AM
Username : Coino
Code : XMAS
Code : XMAS
December 10, 2015, 01:11:25 AM
Username: aRp
Code: XMAS
Code: XMAS
Entered. thanks
You can check the Lottery entrants here : https://docs.google.com/spreadsheets/d/1gM5Ni4SYsmVkMkKZadUvqPODgFX7OdKDckP4jGUp_38/pubhtml?gid=1201634210&single=false
Only the players and participants who have posted your username here will be entered in that order.
December 10, 2015, 01:09:46 AM
Username: aRp
Code: XMAS
Code: XMAS
December 09, 2015, 12:22:45 PM
Appreciating the effort put in by newinbtc, rio3233, shadew, rindo and others. Good luck, may you win the next times.
Loyce is moderator of Rollin, King and Protector of the common folk, A member of the Rollin Brotherhood.
He is also managing this thread along with me. Hadn't mentioned so in the OP because I didn't know back then exactly who will be posting here.
This particular on-thread trivia is copy pasted from his PM to me.
who is LoyceV now never seen in thread @ ndnhc sir
Loyce is moderator of Rollin, King and Protector of the common folk, A member of the Rollin Brotherhood.
He is also managing this thread along with me. Hadn't mentioned so in the OP because I didn't know back then exactly who will be posting here.
This particular on-thread trivia is copy pasted from his PM to me.
December 09, 2015, 12:10:32 PM
my answer : 3368.671952
username: Himea
username: Himea
Wow, that is almost the correct answer!
Since you got close to the answer and posted first, you just got tipped 3 mBTC.
username: skierchewing
Chance to sucessful (5 times) is:
0.49^5 = 0.0282475249, 2.82475249%
Maths:
1 (level 1 - 1% house edge)(total wagered 0mbtc) - bet 100 mbtc at 49 % win = 100 * (100-1) / 49
2 (level 1 - 1% house edge)(total wagered 100mbtc) - bet 202.04081 mbtc at 49 % win = 202.04081 * (100-1) / 49
3 (level 1 - 1% house edge)(total wagered 302.04081mbtc) - bet 408.20490 mbtc at 49 % win = 408.20490 * (100-1) / 49
4 (level 2 - 0.98% house edge)(total wagered 710,24571mbtc) - bet 824.74051 mbtc at 49 % win = 824.74051 * (100-0.98) / 49
5 (level 3 - 0.96% house edge)(total wagered 1534,98622mbtc) - bet 1666,64908 mbtc at 49 % win = 1666,64908 * (100-0.96) / 49
Final Result = 3368,67193 mbtc
Explanation:
why my answer is correct than others..
1. math is right
2. just analyze, rollin only show up 5 decimal digits, it it always round down the number for exemple 100 * (100-1) / 49 = 202,04081632653061224489795918367 = 202,04081
3. this provably is exactly what will show on rollin.io if you play
Chance to sucessful (5 times) is:
0.49^5 = 0.0282475249, 2.82475249%
Maths:
1 (level 1 - 1% house edge)(total wagered 0mbtc) - bet 100 mbtc at 49 % win = 100 * (100-1) / 49
2 (level 1 - 1% house edge)(total wagered 100mbtc) - bet 202.04081 mbtc at 49 % win = 202.04081 * (100-1) / 49
3 (level 1 - 1% house edge)(total wagered 302.04081mbtc) - bet 408.20490 mbtc at 49 % win = 408.20490 * (100-1) / 49
4 (level 2 - 0.98% house edge)(total wagered 710,24571mbtc) - bet 824.74051 mbtc at 49 % win = 824.74051 * (100-0.98) / 49
5 (level 3 - 0.96% house edge)(total wagered 1534,98622mbtc) - bet 1666,64908 mbtc at 49 % win = 1666,64908 * (100-0.96) / 49
Final Result = 3368,67193 mbtc
Explanation:
why my answer is correct than others..
1. math is right
2. just analyze, rollin only show up 5 decimal digits, it it always round down the number for exemple 100 * (100-1) / 49 = 202,04081632653061224489795918367 = 202,04081
3. this provably is exactly what will show on rollin.io if you play
For the accurate answer and nice explanation, the prize of 10 mBTC has been credited to your account.
Congratz.
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