Q.30 - The Practice of Statistics for AP

Question

Whelks and mussels The small round holes you often see in sea shells were drilled by other sea creatures, who ate the former dwellers of the shells. Whelks often drill into mussels, but this behavior appears to be more or less common in different locations. Researchers collected whelk eggs from the coast of Oregon, raised the whelks in the laboratory, then put each whelk in a container with some delicious mussels. Only $9 of 98$ whelks drilled into a mussel.  The researchers want to estimate the proportion $p$ of Oregon whelks that will spontaneously drill into mussels.

Step-by-Step Solution

Answer

All three conditions for confidence interval is not satisfied.

Step-1 Given Information

Given in the question that ,

Number of success$=9$The researchers want to estimate the proportion $p$ of Oregon whelks that will spontaneously drill into mussels.

Step-2 Explanation

To calculate a confidence interval three conditions should be satisfied. The conditions are Random, Independent and Normal.

The condition of random is unknown in the description. Thus, random is not satisfied.

Since the sample size is less than $10\%$ of the population size thus the condition of independent is satisfied.

The survey results the number of success is $9$is less than $10$ thus condition of normal is not satisfied.

Hence, all three conditions for confidence interval is not satisfied.