5. Assuming that the operating income of the head office and branches of the international business is in line with the binary normal distribution, the operating income of the international business head office in 111 year is subject to the normal distribution of the mean value is 170 and the standard deviation is 10. The operating income of the branch is subject to the normal distribution of mean value is 170 and the variance is 10. The correlation coefficient between these two is 0.6. Today, considering a group of international businesses with a total operating income of 175.
Please answer: (10 %)