Step-by-step explanation: The central limit theorem proffers the conditions necessary to obtain a normal or bell shaped distribution. It defines normal distribution in terms of mean, standard deviation and sample size. The sample size is a very important factor in determining the shape of a distribution.
Thus with a population having mean and standard deviation stated, in other to make use of or assume normal distribution, the sample size must be large. According tho the central limit theorem, a size of greater than 30 is deemed to be large enough. As the Same size increases, the sample mean converges to the value of the population mean.
The solution to the system is (90,40)....x = adults and y = child's...so x = 90 (there were 90 adult tickers) and y = 40 (there were 40 child tickets)...u already had the answer right in front of you