help please computerized answer and complete the solution

6. A new rocket-launching system is being considered for deployment of small, short-range rockets. The existing system has p = 0.8 as the probability of a successful launch. A sample of 40 experimental launches is made with the new system, and 34 are successful. Using 95% confidence, the confidence interval is 0.85 + 0.111. What is the sample size required @ 90% level of confidence