Hi, need help for this Question A new device called as "Device C" that relies on flashes of light to calculate a baby's bilirubin level. In a sample

Hi, need help for this Question

A new device called as "Device C" that relies on flashes of light to calculate a baby's bilirubin level.

In a sample of baby girls, the correlation coefficient between bilirubin level from transcutaneous bilirubinometer and the traditional heel prick test is 0.99.

In a sample of baby boys, the correlation coefficient is also 0.99.

If combine the two samples together and calculate the correlation, what would the correlation coefficient be in the combined sample? Please provide the step and reason