Poission leading to binomial

[balmy flume]

confused on y we use a possion of 4 and not a poission of 10. Since each fishing trips last 2 hours so don't we do 5x2=10. Help.

[upper forge]

im not sure if i dont understand you but what your saying dosent make sense

why would multiplying the number of trips by the rate at which you catch fish give you your mean?

in one hour the avg is 2

so x~po(2)

^^ thats in one hour

[balmy flume]

yh i get that

[upper forge]

however each trip is 2 hours

[upper forge]

so ur average would be this doubled

because thats opne hour

and u catch 2

so in 2 hours

u would on average catch 4

[balmy flume]

this the bit i'm confused about

we have 5 trips

[upper forge]

essentially

[balmy flume]

each trips last 2 hours

[upper forge]

yes

dyu understand why it becomes a binomial?

[balmy flume]

yh- my teacher didn't cover this topic but yh i got the gist from doing similar questions

[upper forge]

oh wait i think i understand why u did 5x2

[upper forge]

alright

well essentially

the question asks for how many times out the 5 trips

does the fisher catch at least 5 fish

so its asking for the probability of it happening 3 times out the 5 trips

so we got a fixed number of trials

which is 5

[balmy flume]

yh

[upper forge]

and we can find the probability

dyu know how to?

[balmy flume]

well u can find the probability of there being at least 5

by using a possion model

[upper forge]

exactly

but it has to be the poisson model for 2 hours

[balmy flume]

btw

does the whole 5 trip

last 2 hours

[upper forge]

no each trip is 2 hrs

[balmy flume]

cuz i'm more confused how long that trip lasts

[upper forge]

each individual trip is 2 hours

so when u find the probaility

just use one trip

which would be 2 hrs

[balmy flume]

oh i see

[upper forge]

so your average rate would be multiplied by 2

[balmy flume]

yh makes sense

ty