Sherry and Karl both started their hike with a small bottle filled with water. Tia started her hike with a larger that was 1/2 full. At the end of the hike, Sherry and Tia’s bottles were each half filled with water. Karl’s bottle was filled 1/3 filled with water. Who has the most water left? Construct a math argument to support your answer.

7 weeks

step-by-step explanation:

convert each fraction to the least common multiple of 20, so 3/4 = 15/20 & 1/10 = 2/20, then divide 15 by 2 and you get a little over 7, so the food will last 7 weeks.

ending amount = beginning amount / (2^n)

where "n" = number of half-lives (or elapsed time / half-life)

ending amount = 50 mg / (2 ^10 / 5.3)

ending amount = 50 mg / (2 ^ 1.8867924528)

ending amount = 50 m / 3.6981210597

ending amount = 13.5203794557 mg

or about 13.5 mg remain

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