Which statement about calculating WBC counts is true?

Which statement about calculating WBC counts is true?

• A. The average is obtained by multiplying the sum of counts by ten.
• B. The average is obtained by dividing the sum of counts by ten.
• C. The average is obtained by multiplying the sum of counts by 2000.
• D. The average is obtained by dividing the sum of counts by 100.

Answer: (B)

When you count white blood cells with a hemocytometer, you gather counts from a defined set of squares and then determine the average number of cells per square by dividing the total across those squares by how many squares you counted. If ten squares were counted, the average is the total divided by ten. This approach standardizes the result so you can convert the average per square into a concentration using the known volume that each square represents. Dividing by a different number or multiplying by a factor would not reflect the actual average per square in this counting method, so those options don’t fit.

When you count white blood cells with a hemocytometer, you gather counts from a defined set of squares and then determine the average number of cells per square by dividing the total across those squares by how many squares you counted. If ten squares were counted, the average is the total divided by ten. This approach standardizes the result so you can convert the average per square into a concentration using the known volume that each square represents. Dividing by a different number or multiplying by a factor would not reflect the actual average per square in this counting method, so those options don’t fit.