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3 years ago

12

Mandy begins bicycling West at 30 miles per hour at 11:00 am. If Liz leaves from the same point 20 minutes later bicycling West

at 36 miles per hour, when will she catch Mandy?
A. 2:00 pm
B. 1:00 pm
C. 1:30 pm
D. 2:30 pm

1 answer:

const2013 [10]3 years ago

7 0

36(t - 1/3) = 30t

36t - 12 = 30t

6t = 12

t = 2

2 hours past 11AM is 1PM. So Liz catches

Mandy at 1PM.

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3 years ago

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4. The distribution of blood cholesterol level in the population of young men aged 20 to 34 years is close to Normal, with mean

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Answer:

a) 38.59% probability that a young man (aged 20 to 34) has a cholesterol level greater than 200 milligrams per deciliter.

b) By the Central Limit Theorem, the mean of the distribution of the sample mean would be 188 milligrams per deciliter

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

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This is 1 subtracted by the pvalue of Z when X = 200. So

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1 - 0.6141 = 0.3859

38.59% probability that a young man (aged 20 to 34) has a cholesterol level greater than 200 milligrams per deciliter.

b. Suppose you measure the cholesterol level of 100 young men chosen at random and calculate the sample mean. If you did this many times, i. what would be the mean of the distribution of the sample mean

By the Central Limit Theorem, the mean of the distribution of the sample mean would be 188 milligrams per deciliter

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