Question

A human body contains about 2.7 x 10^4 microliters of blood for each pound of body weight. Each microliter of blood contains about 7 x 10^4 white blood cells. About how many white blood cells are in the body of a 140-lb person?

Answer 1

To calculate the white blood cells in a 140-lb person, multiply the blood volume (2.7 x 10^4 microliters/lb x 140 lb = 3.78 x 10^6 microliters) by the white blood cells per microliter (7 x 10^4) to get approximately 2.646 x 10^11 white blood cells.

Step-by-step explanation:

To calculate the number of white blood cells in the body of a 140-lb person, we first determine the total volume of blood such a person has. The human body contains about 2.7 x 104 microliters of blood for each pound of body weight. For a 140-lb person, this translates to:

2.7 x 104 microliters/lb x 140 lb = 3.78 x 106 microliters of blood

Given each microliter of blood contains about 7 x 104 white blood cells, we can find the total count of white blood cells:

7 x 104 white blood cells/µl x 3.78 x 106 µl = 2.646 x 1011 white blood cells

So, a 140-lb person has approximately 2.646 x 1011 white blood cells.

Answer 2

Step 1:
Find how many microliters of blood there are in a 140lb person.

=140 * (2.7*10^4)
=140*(2.7*10*10*10*10)
=140*27,000
=3,780,000 # of microliters of blood in a 140lb person

Step 2:
Find how many white blood cells in a 140lb person

=3,780,000* (7*10^4)
=3,780,000*(7*10*10*10*10)
=3,780,000*(70,000)
=264,600,000,000 # of white blood cells in a 140lb person

(or 2.646 * 10^11 using scientific notation)


Hope this helps! :)