the volume of blood in a persons body is proportional to body weight. a person who 170 pounds has approximately 5 quarts of blood. estimate the number of quarts of blood in a person who weighs 140 pounds. Complete the proportion, where the ratios have volumes of blood in the numerators and body weights in the denominators. \[ \frac{x}{\square}=\frac{\square}{\square} \] (Do not simplify.)

Step 1 ：The problem is asking to find the volume of blood in a person's body who weighs 140 pounds. We know that the volume of blood in a person's body is proportional to body weight. This means that the ratio of blood volume to body weight is constant.

Step 2 ：We can set up a proportion to solve this problem. The proportion is: \[\frac{Blood\ volume\ of\ 170\ pound\ person}{Weight\ of\ 170\ pound\ person} = \frac{Blood\ volume\ of\ 140\ pound\ person}{Weight\ of\ 140\ pound\ person}\]

Step 3 ：We know that a person who weighs 170 pounds has approximately 5 quarts of blood. So, we can substitute these values into the proportion: \[\frac{5\ quarts}{170\ pounds} = \frac{x\ quarts}{140\ pounds}\] where x is the volume of blood in a person who weighs 140 pounds.

Step 4 ：We can solve this equation for x to find the volume of blood in a person who weighs 140 pounds.

Step 5 ：Final Answer: The estimated number of quarts of blood in a person who weighs 140 pounds is approximately \(\boxed{4.12}\).