Question

A toy manufacturer wants to know how many new toys children buy each year. She thinks the mean is 8 toys per year.Assume a previous study found the standard deviation to be 1.9. How large of a sample would be required in order to estimate the mean number of toys bought per child at the 99% confidence level with an error of at most 0.13 toys? (Round your answer up to the next integer)

Fig: 1