To find the area of a triangle, multiply the base by the height, and then divide by 2. The division by 2 comes from the fact that a parallelogram can be divided into 2 triangles. For example, in the diagram to the left, the area of each triangle is equal to one-half the area of the parallelogram.
Step-by-step explanation:
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Answer:
(a) 2%
Step-by-step explanation:
A score of 60 is 2 standard deviations below the mean (80 -2·10 = 60). The empirical rule tells you that 95% of the distribution is within 2 standard deviations of the mean. The remaining 5% is split evenly between those that are more than 2 SD above the mean and those that are more than 2 SD below the mean.
That tells you the percentage who failed is about 2.5%. The best answer choice is 2%.
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<em>Additional comment</em>
The empirical rule is a little bit sloppy, but it gets you in the ballpark. The actual percentage is closer to 2.275%.
