The scatterplot shows the relationship between economic status measured as a percentage of children in a neighborhood receiving reduced-fee lunch at school and the percentage of bike riders in the neighborhood wearing helmets. The average percentage of children receiving reduced-fee lunches is 30.8% with a standard deviation of 26.7%. The average percentage of bike riders wearing helmets is 38.8% with a standard deviation of 16.9%.
a) If R2 for the least-squares regression line is 72%, what is the correlation between the variables? (Give your answer to two decimal places.)
R =
b) Calculate the slope and intercept for the least-squares regression line for these data.
Slope =
Intercept =
c) What would the value of the residual be in a neighborhood where 45% of the children receive reduced-fee lunch and 42% of the bike riders wear helmets? (Give your answer to 2 decimal places).
Residual =
