Question

a scientist wants to find the average mass of fish living in a large pond. so she will use the masses of a sample of fish from the pond to find the average mass.
answer the questions below.
(a) which unit(s) could be used for the unit of measurement? check all that apply.
kilograms
grams
centimeters
meters
milligrams
(b) which of the procedures below would be the best way to find the average mass?
pick 52 fish from a shallow region of the pond and estimate their masses.
pick 7 fish from a shallow region of the pond and weigh each of them.
randomly pick 52 fish from the entire pond and measure their masses.
randomly pick 7 fish from the entire pond and estimate their masses.

Explanation:

(a) For measuring fish mass, kilograms and grams are appropriate mass units; centimeters/meters measure length, milligrams are too small for typical fish mass.
(b) To estimate average mass of all fish in the pond, a random sample from the entire pond is representative. A small random sample is practical and avoids bias from a single region, while sampling all 52 fish is unnecessary for estimation.

Answer:

(a)

• $\boldsymbol{\circ}$ kilograms
• $\boldsymbol{\circ}$ grams

(b)

• $\boldsymbol{\circ}$ Randomly pick 7 fish from the entire pond and estimate their masses.