In Brianna’s school, grades are calculated as follows: 60% from tests, 25% from homework, and 15% from in-class assignments. (Grades can be considered as expected values of a continuous random variable, but not necessarily normally distributed.) If Brianna’s test total is 84 out of 100, her homework score is 91 out of 100, and her in-class grade is 75 out of 100, what is her grade average?

Suppose babies born after a gestation period of 32 to 35 weeks have a mean weight of 25002500 grams and a standard deviation of 800800 grams while babies born after a gestation period of 40 weeks have a mean weight of 27002700 grams and a standard deviation of 385385 grams. if a 3232-week gestation period baby weighs 21252125 grams and a 4040-week gestation period baby weighs 23252325 grams, find the corresponding z-scores. which baby weighs lessless relative to the gestation period?