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.

Question

Write and solve an exponential equation to determine after which round, x, there are 16 teams left.

Answer 1

16 = 128(0.5)^x

2⁴ = 2⁷(0.5)^x

2^-3 = (2^-1)^x

-3 = -x

3 = x