Answer all 3 parts 25 points a teacher surveyed her class after they had taken a vocabulary test. eighteen of the students claimed they had studied at least one hour for the test. the remaining twelve students admitted that they had not studied for the test at all. the test results (expressed as a percent) for the two groups are shown below. studied: 87, 100, 94, 79, 92, 100, 95, 83, 89, 99, 100, 91, 89, 95, 100, 93, 96, 83 did not study: 82, 72, 45, 91, 58, 83, 65, 87, 90, 77, 73, 89 part 1: calculate the mean of the group that did not study, rounded to the nearest tenth. part 2: calculate the mean absolute deviation of the group that did not study, rounded to the nearest tenth. part 3: how many of the scores (from the group that did not study) are more than two mean absolute deviations from the mean?

geometry: triangles

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call the larger triangle abc

then the smaller triangle cde is similar to abc (all angles are equal, aaa).  

ab is the side that is 36, and we wish to find de, the side corresponding to ab

area_cde = area_abc - area_cde --> area_abc / area_cde = 2

let x=length of de

ratio of areas = (ratio of sides)^2

+2+=+%2836%2fx%29%5e2+

+2+=+1296%2fx%5e2+

++x%5e2+=+1296%2f2+=+648+

25.45584

the area of a triangle is determined by the formula: base x height * 1/2

you'll need to assign a base to the triangle. based on the vertices given, the simplest base would be the line segment from (-2,1) to (2,1). the distance between any two numbers is found by just subtracting them. here, you should subtract the x values to find the distance of this side.

2 - (-2) = 4.

so the distance (aka the length of the base) is 4. the height of the triangle is the distance between the base and the highest point on the triangle which is (3,4). we should subtract the y values this time to find the height/distance.

4 - 1 = 3

so the height is 3.

base = 4

height = 3

hope this if needed hmu