Suppose that in a certain population of adult males, the variable x = "total serum cholesterol level (mg/dl)" is found to be normally distributed, with mean = 220 and standard deviation = 40.(a) suppose that a random sample of n = 36 males is to be selected from this population, and the sample mean cholesterol level calculated. what is the probability that this sample mean value is between 202 and 238? (b) how large a sample size n is necessary to guarantee that 80% of the sample mean values are within 5 mg/dl of the mean of their distribution? (hint: first find the value of z that satisfies p(? z ? z ? +z) = 0.8, then change back to x, and solve for n.)

Ican interpret and represent the remainder in division calculations sensibly for the context (eg if we wont to know how many 40 seat buses will be needed to transport 170 students for on excursion, we divide 170 by 40 and realise buses and another smaller vehicle to that we need 4 transport 10 more students) solve the following questions. show your work! 11) the zoo had 420 butterflies that needed to be transported to a new enclosure. the boxes that the butterflies would be moved in only hold 80 butterflies in each. how many boxes would they need? 2 12) each classroom in the school can have exactly 25 students, if there are 345 students in the school how many full classrooms are there?