A human hair has a diameter of about 4×10

Question

−3
inches. A fingernail is about 0.011 inches thicker. How thick is a fingernail? Write your answer as a decimal to 3 places.
(1 point)

____ inches

Answer 1

To find the thickness of a fingernail, we can start with the diameter of a human hair and add the thickness difference.

1. The diameter of a human hair is approximately \( 4 \times 10^{-3} \) inches, which can be expressed in decimal form as: \[ 4 \times 10^{-3} = 0.004 \text{ inches} \]

2. A fingernail is about \( 0.011 \) inches thicker than the human hair. Therefore, we can calculate the thickness of the fingernail as follows: \[ \text{Thickness of fingernail} = \text{Thickness of human hair} + \text{Difference in thickness} \] \[ \text{Thickness of fingernail} = 0.004 + 0.011 = 0.015 \text{ inches} \]

Now, we round this to three decimal places: \[ 0.015 \]

So, the thickness of a fingernail is \( \boxed{0.015} \) inches.