To find the weight of water in an Olympic-sized swimming pool, we can use the following information:
- The weight of one gallon of water is approximately 8.3 pounds.
- An Olympic-sized swimming pool holds about \( 6.6 \times 10^5 \) gallons.
Now, we can calculate the total weight of the water in the swimming pool:
\[ \text{Weight of water} = \text{Number of gallons} \times \text{Weight per gallon} \]
Substituting the values:
\[ \text{Weight of water} = (6.6 \times 10^5 \text{ gallons}) \times (8.3 \text{ pounds/gallon}) \]
Calculating this:
\[ \text{Weight of water} = 6.6 \times 8.3 \times 10^5 \]
First, calculate \( 6.6 \times 8.3 \):
\[ 6.6 \times 8.3 = 54.78 \]
Now, including the power of 10:
\[ \text{Weight of water} = 54.78 \times 10^5 \text{ pounds} \]
To write this in proper scientific notation, we can express \( 54.78 \) as \( 5.478 \times 10^1 \) so:
\[ 54.78 \times 10^5 = 5.478 \times 10^1 \times 10^5 = 5.478 \times 10^{6} \]
Thus, the approximate weight of water in an Olympic-sized swimming pool is:
\[ \text{Weight of water} \approx 5.478 \times 10^6 \text{ pounds} \]
The correct answer is:
D. 5.478×10^6 pounds