Question

question #11
a pharmaceutical company manufactures medicine to reduce pain caused by migraine headaches. the company is investigating whether a new medicine is more effective in reducing pain than the current medicine. a random sample of 500 participants who experience migraines was selected, and the participants were randomly assigned to one of two groups of equal size. the first group received the current medicine and the second group received the new medicine. when a participant experienced a migraine, he or she was instructed to take the medicine and, 15 minutes after taking the medicine, to rate the pain relief on a scale from 1 to 10, with 1 being no relief to 10 being complete relief. at the end of six months, the average pain relief for each participant was calculated. which of the following is the best description of the study?
○ an experiment using a matched - pairs design.
○ an observational study using a stratified sample.
○ an observational study using a simple random sample.
○ an experiment using a completely randomized design.

question #12
a study is conducted to determine the average pounds of corn produced per acre of farmland. a random sample of local corn farms are selected to report their annual yield of corn production and the size of their farm in acres.
which sampling method describes this situation?
○ cluster sampling
○ random sampling
○ convenience sampling
○ stratified sampling

Explanation:

Question #11

• Matched - pairs design: Requires pairing of participants (not done here).
• Observational study: No intervention (here, new medicine is an intervention).
• Completely randomized design: Participants are randomly assigned to groups (current vs new medicine), which fits the study.

• Cluster Sampling: Involves sampling clusters (not just farms).
• Convenience Sampling: Based on ease (not random).
• Stratified Sampling: Divides population into strata (not done).
• Random Sampling: Selects a random sample (as described: random sample of local corn farms).

Answer:

An experiment using a completely randomized design.

Question #12