Sorry for posting this one again. But sir, Im really sorry. I thought tutors wont answer me, so I do it with different subject. This is really desperate. I didn't know it was dawn there. My country is night right now. Once again sorry. Heres the question.

Plastic drinking straws are manufactured to fit into drinks cartons which have a hole in the top. A straw fits into the hole if the diameter of the straw is less than 3 mm. The diameters of the straws have a normal distribution with mean 2.6 mm and standard deviation 0.25 mm.

- 500 straws are chosen at random. Use a suitable approximation to find the probability that at least 480 straws fit into the holes in drinks cartons.

Im begging, answer me please. :'(

If this much time has passed with no response, it is usually an indication that no one is sufficiently versed in statistics and probability theory that they feel they can provide useful help. I know that I'd have to review my textbooks to work it out.

Believe it or not, we really do try to help with questions, but it's no use just to log in and say, "I can't help you."

So, do what I'd have to do: google some keywords. I'd be willing to bet that a similar question has been asked and answered in other venues.