10000 coins are tossed a what is the probability that betwee

10,000 coins are tossed

a) what is the probability that between 4950 and 5050 of them fall heads

b) Between 4850 and 5150

c)Between 4995 and 5005

Solution

Mean = 10000 * 1/2 = 5000

SD = ?[10000 * (1/2) * (1/2)] = 50.

So for a, you want the part of the normal curve betwen -1 and +1 SD. That is .3413 + .3413 = .6826.

For b, you want the part of the normal curve betwen -3 and +3 SD. That is .4987 + .4987 = .9974

For c, you want the part of the normal curve between -.1 and +.1 SD. That is .0398 + .0398 = .0796.