probability

p = 1/60000
calculate the probability of no failures in 25 attempts

then calculate the probability of at least one failure in 25 attempts

i need help please.... :?:

probability of sucess=p
probability of failure,q=[1-p]

probability of 25 failures, p^0 q^25

=========================================================================
probability of 1 sucess,and 24 failures q^24 p but the sucess could occur in any of 25 trials
probability = 25 p q^24

Arthur

arthur can't i use poisson distribution or is this more binomial distribution. i can run megastat on excel to obtain the value
please help me....