Three blocks a, b, and c and a grooved block d have dimensions a, b, c, and d as follows: a 5 1.500 6 0.001 in b 5 2.000 6 0.003 in c 5 3.000 6 0.004 in d 5 6.520 6 0.010 in d a b b c d a w c (a) determine the mean gap w and its tolerance. (b) determine the mean size of d that will assure that w $ 0.010 in.

solution:

a)  The mean value of gap w̅ is given by,

w̅= d̅ - a̅ - b̅ - c̅

w̅=06.520-0.150-2.000-3.000

w̅=0.020 in

bilateral tolerances of the gap is given by,

tw = ∑t

tw  = 0.001+0.003+0.004+0.010= 0.018 in

w = 0.020 ± 0.018 in

b)  if wmin =0.010 in , then

   w̅ = wmin + tw

   w̅ = 0.010+ 0.018=0.028 in

mean size of d is

d̅ = a̅ + b̅+ c̅+ w̅

d̅ =1.500+2.000+3.000+0.028

  = 6.528 in

describing distributions is one of the key skills you’ll need to earn a high score on the ap statistics exam. if you need proof of this, just flip through some past exam questions, which can be found at the collegeboard website. you’ll notice that the first free response question is almost always a question requiring you to look at a graph and describe it.

step-by-step explanation: just trying to get points sorry : (

the results from a pre-test for students for the year 2000 and the year 2010 are illustrated in the box plot. what do these results tell us about how students performed on the 29 question pre-test for the two years?

if we compare only the lowest and highest scores between the two years, we might conclude that the students in 2010 did better than the students in 2010. this conclusion seems to follow since the lowest score of 8 in 2010 is greater in value than the lowest score of 6 in 2000. also, the highest score of 28 in 2010 is greater in value than the highest score of 27 in 2000.

but the box portion of the illustration gives us more detailed information. the middle bar in each box shows us that the median score of 20 in 2000 is greater in value than the median score of 17 in 2010. further, we note that the box and whiskers divide the illustration into four pieces. each of these four pieces represents the same portion of students. so, the upper half of the students in 2000 scored in the same score range as the upper one-fourth of the students in 2010, see the illustration at a score of 20.

by considering the upper one-fourth, upper half, and upper three-fourths instead of just the lowest and highest scores, we would conclude that the students as a whole did much better in 2000 than in 2010. we would conclude that as a whole the students in 2010 are less prepared than the students in 2000.

in this section, we discuss box-and-whisker plots and the five key values used in constructing a box-and-whisker plot. the key values are called a five-number summary, which consists of the minimum, first quartile, median, third quartile, and maximum.

step-by-step explanation: