A traffic consultant wants to estimate the true proportion of cars on a certain street that have more than two occupants. She stands at the side of the road for two hours on a weekday afternoon and flips a coin each time a car approaches. If the coin comes up heads, she counts the number of occupants in the car. After two hours, she has counted 103 cars, 15 of which had more than two occupants. Which condition for constructing a confidence interval for a proportion has she failed to satisfy

The data is a simple random sample from the population of interest.

Step-by-step explanation:

Conditions necessary to consider when constructing a confidence interval include using a large sample size, which should be greater Than or equal to 30 for n and a sample proportion of np ≤ 10. Importantly the sample must be a random sample drawn from the population, meaning that all the population of interest must have equal chances of being a part of the sample data. However, the scenariomabiveb, violates this condition as the sampling design is not completely randomized. Those who do not ply the route on that certain day have no Chaves of being part of the sample.

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+

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