2016 AMC 8 Problem 16

Attempt Problem 16 of the 2016 AMC 8 below, then check your answer against the video solution and professionally curated solution from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2016 AMC 8 solutions, or check the answer key.

All problems are used with official legal permission of the Mathematical Association of America (MAA).

16.

Annie and Bonnie are running laps around a 400400-meter oval track. They started together, but Annie has pulled ahead, because she runs 25%25\% faster than Bonnie. How many laps will Annie have run when she first passes Bonnie?

114 1\dfrac{1}{4}

313 3\dfrac{1}{3}

4 4

5 5

25 25

Answer: D
Concepts:relative speeddistance rate and timeratio and proportion
Difficulty rating: 1240
Video solution:
Solution video thumbnail
Play video

Click to load, then click again to play

Written solution:

Since Annie is 25%25\% faster than Bonnie, for every lap Bonnie finishes, Annie completes 1141 \dfrac{1}{4} laps. Therefore, Annie gains a quarter lap every time Bonnie finishes a lap.

With this in mind, for Annie to completely lap Bonnie, Bonnie must finish 44 laps, which means that Annie finished 55 laps.

Thus, D is the correct answer.

← Problem 15#15
Full Exam

Problem 16 in Other Years

1985 AMC 8 · 1986 AMC 8 · 1987 AMC 8 · 1988 AMC 8 · 1989 AMC 8 · 1990 AMC 8 · 1991 AMC 8 · 1992 AMC 8 · 1993 AMC 8 · 1994 AMC 8 · 1995 AMC 8 · 1996 AMC 8 · 1997 AMC 8 · 1998 AMC 8 · 1999 AMC 8 · 2000 AMC 8 · 2001 AMC 8 · 2002 AMC 8 · 2003 AMC 8 · 2004 AMC 8 · 2005 AMC 8 · 2006 AMC 8 · 2007 AMC 8 · 2008 AMC 8 · 2009 AMC 8 · 2010 AMC 8 · 2011 AMC 8 · 2012 AMC 8 · 2013 AMC 8 · 2014 AMC 8 · 2015 AMC 8 · 2017 AMC 8 · 2018 AMC 8 · 2019 AMC 8 · 2020 AMC 8 · 2022 AMC 8 · 2023 AMC 8 · 2024 AMC 8 · 2025 AMC 8 · 2026 AMC 8