i have homework to do. this is the only way i can see the questions. sorry.
1The random variable R has the binomial distribution B(12, 0.35).
(a) Find P(R ³ 4).
(2)
The random variable S has the Poisson distribution with mean 2.71.
(b) Find P(S £ 1).
(3)
The random variable T has the normal distribution N(25, 52).
(c) Find P(T £ 18).
(2)
2Minor defects occur in a particular make of carpet at a mean rate of 0.05 per m2.
(a) Suggest a suitable model for the distribution of the number of defects in this make of carpet. Give a reason for your answer.
A carpet fitter has a contract to fit this carpet in a small hotel. The hotel foyer requires 30 m2 of this carpet. Find the probability that the foyer carpet contains
(b) exactly 2 defects,
(3)
(c) more than 5 defects.
(3)
3. Vehicles pass a particular point on a road at a rate of 51 vehicles per hour.
(a) Give two reasons to support the use of the Poisson distribution as a suitable model for the number of vehicles passing this point.
(2)
Find the probability that in any randomly selected 10 minute interval
(b) exactly 6 cars pass this point,
(3)
(c) at least 9 cars pass this point.
(2)