Rulɛt matematiks · Mat prɔblɛm · 7 minit

Prɔblɛm: aw lɔng te ziro kam

Ziro de kam wan spin insay 37 pan avrej. Aw lɔng yu rili de wet, ɛn wetin dat de du to pɔsin we de bɛt ivin mɔni?

Shɔt ansa

Di wet fɔ ziro na jiomɛtrik: avrej 37 spin, midul valyu 25, ɛn wan wet insay twɛnti de pas 110 spin. Insay sɛshɔn fɔ 200 spin, pɔsin we de bɛt ivin mɔni fɔ ɛkspɛkt 5.4 ziro, ɛn i go si ɛnisay frɔm 1 to 10.

avrej wet
37 spin
midul valyu fɔ di wet
25 spin
p(no ziro insay 100 spin)
6.5%
ziro insay 200 spin
5.4 ± 2.3

Di prɔblɛm

ZirowilZiroDi wan grin pɔkit we nɔ ivin-mɔni, dɔzin ɔ kɔlɔm bɛt nɔ kɔba; na usay di kasino advantej kɔmɔt. Dɛn kin kɔl am bak: wan ziro, 0.Rid ɔl → gɛt prɔbabilitimatematiksPrɔbabilitiDi chans fɔ wan rizɔlt, frɔm 0 to 1 ɔ frɔm 0% to 100%. Wan nɔmba: 1/37 = 2.70%.Rid ɔl → 1/37 fɔ ɛni spin. (a) Wetin na di prɔbabiliti se ziro nɔ go kam insay di nɛks 37 spin? (b) Wetin na di midul valyu fɔ di wet? (c) Insay ivin-mɔni sɛshɔn fɔ 200 spin, ɔmɔs ziro pleya fɔ ɛkspɛkt, ɛn frɔm ɔmɔs to ɔmɔs?

Di ansa dɛn

(a) (36/37)³⁷ = 36.3%. Mɔ pas wan tɔd pan di tɛm, 37 spin de pas ɛn ziro nɔ kam atɔl; na di sem kalkuleshɔn we mek “fɔ nak wan tɛm wit bɛt pan wan nɔmbabɛtBɛt pan wan nɔmbaWan nɔmba nɔmɔ, i de pe 35:1.Rid ɔl → insay 37 spin” na jɔs 63.7%. (b) Di wet W na jiomɛtrik; p(W > k) = (36/37)ᵏ; di midul valyu na di k usay dis krɔs 0.5, we na k ≈ 25. Af pan di wet dɛn na 25 spin ɔ shɔt pas dat, ɛn af lɔng pas dat; di lɔng tel de pul di avrej 37 go ɔp. (c) Ziro insay 200 spin na binomial wit avrej 200/37 = 5.4 ɛn standad diviyeshɔnmatematiksStandad diviyeshɔnDi skwɛ rut fɔ varians; di nɔmal distans bitwin wan rizɔlt ɛn di valyu we fɔ ɛkspɛkt.Rid ɔl → √(200 × (1/37) × (36/37)) ≈ 2.3. Di 95% rɛnj na lɛk 1 to 10.

wet fɔ ziroprɔbabiliti
insay 10 spin24.0%
insay 25 spin49.6%
insay 37 spin63.7%
insay 50 spin74.6%
insay 100 spin93.5%
mɔ pas 110 spin≈ 5%
mɔ pas 200 spin0.4%
p(W ≤ k) = 1 − (36/37)ᵏ. Avrej 37, midul valyu 25.

Wetin ziro de kɔst pɔsin we de bɛt ivin mɔni

Ɛni ziro de kɔst wan bɛt mɔni, ɛn ziro na di ol advantej pan rɛdbɛtRɛdIvin-mɔni bɛt pan di 18 rɛd nɔmba. Na Frɛnch: rouge.Rid ɔl →: insay 37 avrej spin, di 18 win ɛn di 18 lɔs de kansɛl, ɛn di wan ziro na di −1/37. Insay sɛshɔn fɔ 200 spin wit $10, di 5.4 ziro we fɔ ɛkspɛkt de kɔst $54, we na ɛgzaktli 200 × $10 / 37. Sɛshɔn we gɛt 2 ziro dɔn gɛt $34 gud lɔk; sɛshɔn we gɛt 9 ziro dɔn gɛt $36 bad lɔk, ɛn i go fil lɛk se dɛn fiks am. Pan la partagerulLa partageFrɛnch rul: if ziro kam, af fɔ di ivin-mɔni bɛt mɔni de kam bak. I de kɔt di kasino advantej pan dɛn bɛt ya to af, 1.35%.Rid ɔl → tebul, ɛni ziro de kɔst af bɛt mɔni ɛn di nɔmba dɛn de kɔt na af.

Ziro insay sɛshɔn fɔ 200 spin% pan di sɛshɔn dɛn
0–1
2.5%
2–3
18%
4–5
34%
6–7
28%
8–9
13%
10 ɔ mɔ
4.5%
% pan di sɛshɔn dɛn
01734%
Binomial(200, 1/37). Di pɔsin we de bɛt $10 pan rɛd de pe $10 fɔ ɛni ziro; di sprɛd na di ziro dɛn na di sprɛd na di prays fɔ di ivintɛm.

Di La Partage rul na rulɛtDɛn dɔn fiks ɔnlayn rulɛt? Di lay-lay tɔk

Di kwɛstyɔn we de kam afta

Wetin na di prɔbabiliti fɔ tu ziro wan afta di ɔda? (1/37)² = 1/1,369. Insay kasino we de rɔn 20 tebul wit 50 spin fɔ ɛni awa, dat na lɛk wan pe fɔ ziro bak to bak sɔmwe ɛni 1.4 awa. Pleya dɛn we si am de se di wil dɔn pwɛl; di kalkuleshɔn se na jɔs nɔmal Tyusde.

Tray am

Di Sɛshɔn simulɛta de kɔnt di ziro dɛn fɔ ɛni sɛshɔn. Rɔn 100 spin sɔm ɔndrɛd tɛm ɛn drɔ di kɔnt: di istogram we de ɔp go sho, wit in lɔng tel na di rayt. Na di tel di stori dɛn de kɔmɔt.

Fɔmula

p(W > k) = (36/37)ᵏ
E[W] = 37 · midul valyu ≈ 25
ziro insay N spin ~ Binomial(N, 1/37)

Kwɛstyɔn dɛn

Ziro kin kam mɔ pan sɔm wil?

Nɔto pan fɛr wil. Pan wil we gɛt bayaslabWil we gɛt bayasWil we gɛt pɔblɛm na in bɔdi we mek sɔm pɔkit kin kam pas 1/37. I nɔ kɔmɔn, ɛn yu kin fɛn am nɔmɔ wit tawzin tawzin spin we yu dɔn rayt dɔn.Rid ɔl →, ɛni pɔkitikwipmɛntPɔkitWan pan di 37 smɔl ples dɛn wit nɔmba pan di rotɔ. Dɛn kin kɔl am bak: slot, kɔp.Rid ɔl → kin kam mɔ, ɛn yu go nid tawzin tawzin spin fɔ no.

A fɔ put chip pan ziro ɔltɛm lɛk inshɔrɛns?

I na 2.70% bɛt lɛk ɛni ɔda wan. I de chenj di shep fɔ di sɛshɔn (ziro de tɔn win) ɛn nɔto di kɔst.

Wetin mek di midul valyu smɔl pas di avrej?

Bikɔs di distribyushɔn fɔ di wet dɛn nɔ ivin: bɔku shɔt wet, ɛn sɔm smɔl wan we lɔng bad bad wan.

Smɔl jok fɔ ɛz di maynd

Avrej 37, midul valyu 25, ɛn lɔng tel usay di stori dɛn de liv.

Avrej 37, midul valyu 25, ɛn lɔng tel usay di stori dɛn de liv.

Usay wi gɛt am frɔm

  1. Feller, W. An Introduction to Probability Theory and Its Applications, Vol. 1. Wiley, 3rd ed., 1968. Gambula in rɔin, chapta XIV.
  2. Ethier, S. N. The Doctrine of Chances: Probabilistic Aspects of Gambling. Springer, 2010. Chapta 13, rulɛt.
wi chɛk am 2026-09-28mɔdɛl: Yuropian, wan ziromɛtɔdɔlɔji ↗usay wi gɛt am frɔm ↗