Question

About how many times larger than the diameter of a red blood cell is the diameter of a grain of sand? Write your answer using a power of ten. The red blood cell is 8.4 times 10 to the power of negative 6. The grain of sand is 2.4 times 10 to the power of negative 3. I'm not quite sure how to work this problem out from here.

Answer 1

Answer:

$0.29\cdot10^3$

Step-by-step explanation:

Red blood cell: $8.4\cdot 10^{-6}$

Grain of sand: $2.4\cdot 10^{-3}$

The "how many times larger" part can be figured out by forming a ratio between the two diameters above:

$\frac{2.4\cdot 10^{-3}}{8.4\cdot 10^{-6}} = \frac{2.4}{8.4}\cdot\frac{10^{-3}}{10^{-6}}\approx 0.29\cdot 10^{-3-(-6)}=0.29\cdot10^3$

Note that dividing the powers of ten corresponds to subtracting the denominator power from the numerator power of 10.