The diameter of one red blood cell is about 2.95E-4 of an inch. It would take about 5.35E12 red blood cells laid end to end to span the circumference of the earth.

Question

What would be the length of this chain of red blood cells?
A.
1.814 × 10^9 inches
B.
1.578 × 10^8 inches
C.
1.578 × 10^9 inches
D.
1.814 × 10^8 inches

Answer 1

To find the total length of the red blood cells laid end to end, we can use the following formula:

$$\text{Total Length}=\text{Number of Red Blood Cells}\times \text{Diameter of One Red Blood Cell}$$

Given:

• Number of red blood cells = $5.35\times {10}^{12}$
• Diameter of one red blood cell = $2.95\times {10}^{-4}$ inches

Now, we can calculate the total length as follows:

$$\text{Total Length}=5.35\times {10}^{12}\times 2.95\times {10}^{-4}$$

Now, perform the multiplication:

1. Calculate $5.35\times 2.95$:

   • $5.35\times 2.95=15.8225$

2. Combine the powers of 10:

   • ${10}^{12}\times {10}^{-4}={10}^{12-4}={10}^8$

3. Therefore, the total length becomes: $$\text{Total Length}=15.8225\times {10}^8\text{ inches}$$

Converting $15.8225$ into scientific notation: $$15.8225=1.58225\times {10}^1$$

Thus, updating the expression: $$\text{Total Length}=1.58225\times {10}^1\times {10}^8=1.58225\times {10}^9\text{ inches}$$

Rounding $1.58225$ to three significant figures gives us approximately $1.578\times {10}^9$.

So, the length of this chain of red blood cells is:

C. $1.578\times {10}^9$ inches