Final answer:
The question involves using a regression model to predict sales for a business. On day 60, the sales prediction is 250.12 thousand dollars, and on day 90, it is 324.52 thousand dollars using the given regression equation.
Step-by-step explanation:
The question relates to time series analysis and specifically to forecasting methods. When using single exponential smoothing, the forecast for a future period is calculated by adjusting the forecast for the current period towards the observed value for the current period. This technique is commonly used in business to forecast sales, stock levels, and other time-dependent data. Given a simple linear regression model to predict sales growth, like the one provided (žy = 101.32 + 2.48x), we can calculate predicted sales for specific days.
To predict the sales on day 60 using the model, substitute x = 60 into the model to get žy = 101.32 + (2.48 × 60). Similarly, to predict the sales on day 90, substitute x = 90 into the model to get žy = 101.32 + (2.48 × 90). For day 60, the predicted sales would be žy = 101.32 + 148.8 = 250.12 thousand dollars. For day 90, they would be žy = 101.32 + 223.2 = 324.52 thousand dollars.