How many calls would you expect following an evening with three advertisements?

What proportion of the variation in calls is explained by the number of advertisements?

The number of calls to a call centre dealing with new loan applicants is thought to be influenced by the number of advertisements shown on television the previous night. The regression output is shown below. SUMMARY OUTPUT Regression Statistics Multiple R 0.25 R Square 0.50 Standard Error 92.10 Observations 200 Coefficients P-value Intercept 205.00 0.06 Number of Adverts (x) 37.20 0.40