in a sample of 70 stores of a certain company, 58 violated a scanner accuracy standard. it has been demonstrated that the conditions for a valid large- sample confidence interval for the true proportion of the stores that violates the standard were not met. Determine the number of stores that must be sampled in order to estimate the true proportion to within 0.5 with 90% confidence using the large samplemethod.

1. find the number of stores that must be sampled is - ----------------------