Question

a scientist wants to find the average weight of fish living in a large pond. so she will use the weights of 30 fish from the pond to find the average weight.
answer the questions below.
(a) which unit(s) could be used for the unit of measurement? check all that apply.
□ seconds □ ounces □ hours □ pounds □ minutes
(b) which of the procedures below would be the best way to find the average weight?
○ pick 30 fish from a shallow region of the pond and weigh each of them.
○ pick 30 fish from a shallow region of the pond and estimate their weights.
○ randomly pick 30 fish from the entire pond and estimate their weights.
○ randomly pick 30 fish from the entire pond and weigh each of them.

Explanation:

Part (a)

• Seconds: Unit of time, not weight.
• Ounces: Unit of weight (e.g., for small - to - medium - sized objects like some fish).
• Hours: Unit of time, not weight.
• Pounds: Unit of weight (e.g., for larger fish or groups of fish).
• Minutes: Unit of time, not weight.

Part (b)

• Pick 30 fish from a shallow region and weigh: Sampling only from a shallow region may not represent all fish in the pond (e.g., some fish species may prefer deeper water).
• Pick 30 fish from a shallow region and estimate: Estimating is less accurate than actual weighing, and the shallow - region sampling is biased.
• Randomly pick 30 fish and estimate: Estimating is less accurate than weighing.
• Randomly pick 30 fish and weigh: Random sampling helps to get a representative sample of the fish population in the pond, and weighing gives accurate data for calculating the average.

Answer:

(a) ounces, pounds
(b) Randomly pick 30 fish from the entire pond and weigh each of them.