Question

A scientist measured the diameters of two different types of human hair. The diameter of human hair A was about 6 × 10−4 inch and the diameter of human hair B was about 3 × 10−3 inch.

Which of the following statements is true?

A.
The diameter of human hair B is about two times the diameter of human hair A.
B.
The diameter of human hair A is about five times the diameter of human hair B.
C.
The diameter of human hair A is about two times the diameter of human hair B.
D.
The diameter of human hair B is about five times the diameter of human hair A.

Answer 1

D

Explanation:

hair A : 6 × 10^-4 = 0.0006

hair B : 3 × 10^-3 = 0.003

I think now it is clearer why.

5×0.0006 = 0.003