An economist would like to estimate a 90% confidence interval for the average real estate taxes collected by a small town in California. In a prior analysis, the standard deviation of real estate taxes was reported as $1,590. Use Table 1.

What is the minimum sample size required by the economist if he wants to restrict the margin of error to $490? (Round intermediate calculations to 4 decimal places and "z-value" to 3 decimal places. Round up your answer to the nearest whole number.)