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# So for a binomial distribution if I have to find the P(X <6) ... watch

1. So I would essentially find P(X less than or equal to 5) which is P(X=0)+P(X=1)... Up to P(X=5)

Is there a quicker way to figure it out?
2. (Original post by APersonYo)
So I would essentially find P(X less than or equal to 5) which is P(X=0)+P(X=1)... Up to P(X=5)

Is there a quicker way to figure it out?
Use the cumulative probability table, you need to know the amount of trials and the probability of success and then you can use that to look for the relevant table and look for when x is smaller than or equal to 5
3. (Original post by APersonYo)
So I would essentially find P(X less than or equal to 5) which is P(X=0)+P(X=1)... Up to P(X=5)

Is there a quicker way to figure it out?
In addition to using tables, your calculator may have a cumulative binomial function. If you’re on the new spec then this will be the way you should be doing it.
4. (Original post by Notnek)
In addition to using tables, your calculator may have a cumulative binomial function. If you’re on the new spec then this will be the way you should be doing it.
oooh okay thank you but this is for my degree hahahahahaha
5. (Original post by APersonYo)
So I would essentially find P(X less than or equal to 5) which is P(X=0)+P(X=1)... Up to P(X=5)

Is there a quicker way to figure it out?
In addition to the other suggestions, note that P(X <= 5) is the same as 1 - P(X>5). The latter may be easier to work out (if n is not much more than 5).
Use the cumulative probability table, you need to know the amount of trials and the probability of success and then you can use that to look for the relevant table and look for when x is smaller than or equal to 5
Thank you!
7. It can be solved using binomial table, poission table but depends on what the distribution of x is.

(Original post by APersonYo)
So I would essentially find P(X less than or equal to 5) which is P(X=0)+P(X=1)... Up to P(X=5)

Is there a quicker way to figure it out?

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