Hi There!
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We Know:
Olympic Pool: 8.12 x 105 gallons
Smaller Pool: 5.27 x 105 gallons
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Olympic Pool:
8.12 x 105 = 852.6 gallons.
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Smaller Pool:
5.27 x 105 = 553.35 gallons.
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Together:
852.6 + 553.35 = 1405.95
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Options:
1.339 x 104 = 139.256 (Incorrect)
1.339 x 106 = 141.934 (Incorrect)
13.39 x 1010 = 13523.9 (Incorrect)
1.339 x 1010 = 1352.39 (Closest)
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Answer:
D) 1.339 x 1010 gallons
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Hope This Helps :)