Reference no: EM133265278

Problem:

In 2018, the average performance of college-bound seniors on the Evidence-Based Reading and Writing portion of the SAT followed a normal distribution with mean 522 and standard deviation 114.

1. The mean for the SAT Math portion was 542. What percent of these students scored lower on the Reading and Writing than the mean Math score of 542?
2. What is the probability that a random sample of 5 of these college-bound seniors would have an average Reading a Writing score less than the average Math score of 542?
3. What proportion of these students scored 600 or higher on the Reading and Writing portion?
4. What is the minimum Reading and Writing score of the college-bound seniors who were in the top 5% of all scores on the Reading and Writing portion?
5. What percentage of these students scored between 550 and 650 on the Reading and Writing portion?
6. According to the Mayo Clinic most premature babies are born at the late preterm stage; a late preterm birth occurs when a baby is born between 34 weeks (238 days) and 37 weeks (259 days). What proportion of babies are born during this stage?
7. A very preterm baby is one born at less than 32 weeks. What is the probability that a randomly chosen birth is considered very preterm?
8. Approximately 12.5% of babies in the United States are born premature. According to this value, what would be the maximum length of pregnancy for a prematurely born baby?
9. How long are the longest 1% of pregnancies in the United States?