(a) The data below represents the monthly share price of Sunway Bhd (SWAY) for the past 10 weeks.
(i) Find the mean and sample standard deviation for the above data. ( 5 marks) (ii) Construct a 99\% confidence interval for the true population mean value of Sunway Bhd (SWAY) share price. (iii) An investment agent claims that on average, share price of Sunway Bhd (SWAY) to be more than RM 1.50/ share in recent times. Test the agent's claim at α=0.05, if the elaim is true. (b) (b)Gibbs Baby Food Company wishes to compare the weight gain of infants using its brand versus its competitor's. A sample of 40 babies using the Gibbs products revealed a mean weight gain of 7.7 pounds in the first three months after birth. For the Gibbs brand, the population standard deviation of the sample is 2.2 pounds. A sample of 55 babies using the competitor's brand revealed a mean increase in weight of 8.15 pounds. The population standard deviation is 2.85 pounds. At the 0.05 significance level, can we conclude that babies using the Gibbs brand gained less weight?