A company wants to estimate the fraction theta of defective chips it produces. Say a random sample of 900 chips has 18 defectives. Find a point estimate of theta. Next find a 95% confidence interval for the proportion theta of defective chips and also find a one sided 95% confidence interval for the proportion of defective ones. Refering to this problem, how large a ssample should be taken in order to be confident with probability 95% that the margin of error to estimate the fraction theta of defective chip is 0.025. Refering to this problem, find by how much the sample size increases or decreases if we are willing to increase the margin of error from 0.025 to 0.05 with same 95 probability.