The two lines represent the amount of water, over time, in two tanks that are the same size. Which container is filling more quickly? Explain how you know. Two lines graphed in a coordinate plane labeled "A" and "B". The horizontal axis is labeled "time, in minutes" and the vertical axis is labeled "water, in gallons." Line A begins at the origin and moves steeply upward and to the right. Line B also begins at the origin and moves steadily upward and to the right.

here is a big fat

the 8 in 8,420 is in the thousands place so it's value is 8 thousand.

the 8 in 6,870 is in the hundreds place so it's value is 8 hundred.

divide 8000 by 800 to find the answer:

8000 / 800 = 10

the 8 in 8,420 is 10 times greater than the 8 in 6,870

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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