There are a total of 128 teams at the start of a citywide 3-on-3 basketball tournament. half the teams are eliminated after each round. write and solve an exponential equation to determine after which round, x, there are 16 teams left.

'after the third round'.

Step-by-step explanation:

Let T be the number of teams after n rounds.

T=128\times(\frac{1}{2})^{n}

When T = 16, we get:16=128\times(\frac{1}{2})^{n}

Dividing both sides by 128, we get:

\frac{1}{8}=(\frac{1}{2})^{n}

Therefore n = 3

The answer is 'after the third round'.

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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