Answer:
2.8
Step-by-step explanation:
1) find the mean of the data set. = 15
2) find the abs value of the diff between each data value and the mean: |data value – mean|.
|10-15|=5, |20-15|=5, |15-15|=0, |17-15|=2, |13-15|=2
3) find the sum of the abs values of the diff = 14
4) divide the sum of the abs value by the number of data values = 14/5 = 2.8
120
OA = OB
angle OAN = 90 degrees, so OAB and OBA is both 30 degrees.
When you are dividing fractions you just flip the second fraction upside down and multiply the two fractions
So the first is
½ x 6/1 = 6/2 = 3
For the second you write them as improper fractions then do the same
So it is
3/2 / 1/8 = 3/2 x 8/1 = 24/2 = 12
So the answer to the first question is 3 and the second is 12
<h3>
Answer: 48</h3>
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Explanation:
Triangle ABC is isosceles because AC = BC.
The angles opposite these congruent sides are angle ABC and angle BAC. These are the base angles.
For any isosceles triangle, the base angles are congruent.
Angle BAC = 69 degrees is given. So angle ABC = 69 as well.
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The missing angle must add to the two other angles so that all three angles in a triangle add to 180
(angle ABC) + (angle BAC) + (angle BCA) = 180
69 + 69 + (angle BCA) = 180
138 + (angle BCA) = 180
angle BCA = 180-138
angle BCA = 42
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Angle DCE is congruent to angle BCA because they are vertical angles.
Triangle DCE is a right triangle. The missing angle is 90-(angle BCA) = 90-42 = 48
angle EDC = 48 degrees
15.87% of the population does not meet the minimum standards.
We use z-scores to find this probability:
z=(X-μ)/σ = (85-100)/15 = -15/15 = -1
Using a z-table (http://www.-table.com) we see that the area to the left of, less than, this is 0.1587. This is 15.87%.
