Question

The diameter of a human red blood cell is
\[0.000009 \text{ m}\]. The diameter of a cold virus is
\[0.00000003 \text{ m}\].
Approximately how many times as large is the diameter of a red blood cell as the diameter of a cold virus?
Choose 1 answer:
Choose 1 answer:
(Choice A)
\[3 \cdot 10^{-14}\]
A
\[3 \cdot 10^{-14}\]
(Choice B)
\[3 \cdot 10^{-2}\]
B
\[3 \cdot 10^{-2}\]
(Choice C)
\[3 \cdot 10^1\]
C
\[3 \cdot 10^1\]
(Choice D)
\[3 \cdot 10^2\]
D
\[3 \cdot 10^2\]

Answer 1

To find out how many times as large the diameter of a red blood cell is compared to that of a cold virus, we divide the diameter of the red blood cell by the diameter of the cold virus.

Given:
- Diameter of a red blood cell = \(0.000009\) m = \(9 \times 10^{-6}\) m
- Diameter of a cold virus = \(0.00000003\) m = \(3 \times 10^{-8}\) m

Now we need to calculate:

\[
\text{Ratio} = \frac{\text{Diameter of red blood cell}}{\text{Diameter of cold virus}} = \frac{9 \times 10^{-6}}{3 \times 10^{-8}}
\]

Performing the division:

\[
= \frac{9}{3} \times \frac{10^{-6}}{10^{-8}} = 3 \times 10^{(-6) - (-8)} = 3 \times 10^{2}
\]

Thus, the diameter of a red blood cell is approximately \(3 \times 10^2\) times as large as the diameter of a cold virus.

The correct answer is:

(Choice D) \(3 \cdot 10^2\)