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If you get 13 out of 20 questions correct on a test, what percent grade do you get?

If you buy 212{“version”:”1.1″,”math”:”212″} yards of material for a costume, and then realize you need another 114{“version”:”1.1″,”math”:”114″} yards, how many yards of material do you need all together?

Convert to a decimal, rounded to the nearest hundredth:  711{“version”:”1.1″,”math”:”711″}

The shaded region in the figure represents what fraction of the whole rectangle? (Your answer must be in lowest terms.)

What is 7% of 1400?

Solve for x:  27x=14{“version”:”1.1″,”math”:”27x=14″}

A batch of cookies requires 34{“version”:”1.1″,”math”:”34″} cup of sugar.  How much sugar do you need for half a batch?

Sleep study. Based on the sleep study survival curve, about ______ of individuals in the severe apnea (>30 events/ hour) group had died in 10 years. The remaining subjects in this group who survived are considered to be ___________.  

Approval of the COVID vaccines by the FDA required they be tested in formal clinical trials. Using the COVID vaccines as an example… Identify the various phases of a clinical trial, and for each phase- describe the overall objective, the approximate number of subjects expected to be enrolled, and how the primary and secondary outcomes measured might evolve in each phase to achieve the overall objective. Assume there was no prior experience with mRNA-based vaccines.

  The survival curve above is from a clinical trial testing the difference between 10 and 80 mg of the statin drug Lipitor for the prevention of a Major Cardiovascular Event (MCE). The trial starts with ~5000 subjects in each group, and after 5 years of the trial we can see there are only 2300 individuals remaining in each group who are ‘at risk’- a reduction of just over 50% (~2500 participants in each group). However, if we look closely at the survival curve, only about 10% of subjects (~500 per group) actually experienced an MCE. Using your knowledge of survival analysis, explain and provide some rationale for this apparent discrepancy… i.e. why is there such a dramatic difference in subjects who are no longer on trial because they experienced an MCE (~500 per group) vs. the total number who are no longer ‘at-risk’ (~2500 per group)?