A marketing survey is conducted in which students are to taste two different brands of soft drink. Their task is
to correctly identify the brand tasted. A random sample of 180 students is taken. Assume that the students have no ability to distinguish between the two brands.
The probability is 90% that the sample percentage is contained within what symmetrical limits of the population percentage? Identify the limits of the population percentage. The lower limit is _____ The upper limit is ______