Here's all the answers to the assignment! This is here to help future people in order to get a good grade on e2020! :)
Use the information on the right to determine which students will have positive z-scores.
Answer(s):
B) Benjamin, who completed the exam in 86 minutes
C) Cynthia, who completed the exam in 72 minutes
Cynthia’s z-score is
Answer) 0.2
A newborn who weighs 2,500 g or less has a low birth weight. Use the information on the right to find the z-score of a 2,500 g baby.
Answer) -2
What is the z-score of a newborn who weighs 4,000 g?
Answer) 1
What weight would give a newborn a z-score of −0.75?
Answer) 3125
In the United States, birth weights of newborn babies are approximately normally distributed with a mean of ? = 3,500 g and a standard deviation of ? = 500 g.
According to the empirical rule, 68% of all newborn babies in the United States weigh between
Answer(s) 3000 g and 4000 g
95% of all newborn babies in the United States weigh between
Answer(s) 2500 g and 4500 g.
99.7% of all newborn babies in the United States weigh between
Answer(s) 2000 g and 5000 g.
According to the empirical rule, 68% of 7-year-old children are between
Answer(s) 47 inches and 51 inches tall.
95% of 7-year-old children are between
Answer(s) 45 inches and 53 inches tall.
99.7% of 7-year-old children are between
Answer(s) 43 inches and 55 inches tall.
Use the information given in the table on the right to complete each of the following statements.
Brenda is 50 inches tall. Her z-score is
Answer) 0.5
Zach has a z-score of –1.5. His height is
Answer) 46 inches.
Approximately <u>
16
%</u> of 7-year-old children are taller than 51 inches.
In the United States, birth weights of newborn babies are approximately normally distributed with a mean of μ = 3,500 g and a standard deviation of σ = 500 g.
What percent of babies born in the United States are classified as having a low birth weight (< 2,500 g)? Explain how you got your answer.
(Answers)
The z-score for 2,500 g is –2.
According to the empirical rule, 95% of babies have a birth weight of between 2,500 g and 4,500 g.
5% of babies have a birth weight of less than 2,500 g or greater than 4,500 g.
Normal distributions are symmetric, so 2.5% of babies weigh less than 2,500g.
