Sanwar has a lot of time on his hands so he starst to toss a

Sanwar has a lot of time on his hands, so he starst to toss a coin and count the number of times it comes up heads. HE finds that out of 1000 tosses, he gets heads 487 times and tails 513 times.

a) calculate the experimental probability of getting heads when tossing the coin.

b) Explain wheather or not you think the coin he was tossing was a fair coin.

c) Sanwar nitices a strange thing: his last eight tosses were all tails. If he were to toss it one more time, do you think it would more likely come up heads or tails?Explain.

Solution

n =1000 tosses

no of heads = 487

experimental prob = 0.487

If fair coin prob for heads = 0.5

Let us set null and alternate to check whether coin is fair

H0: p = 0.5

Ha: p <0.5

Left tailed test.

std error^2 = 0.5(0.5)/1000

std error = 0.0158

z statistic =  = -0.823

p value = 0.2053

As p >0.05, accept null hypothesis.

The coin is fair.

As each outcome in the toss of coin is independent of the previous trials, we cannot predict anything about the 9th toss.