Source: Manhattan Prep
The figure below represents a track with identical semi-circular ends used for a 4-lap relay race involving two 4-person teams (where each team member runs one complete lap around the track). The table below shows the lap times for each runner on Team A and Team B. Assuming that each runner runs at a constant rate, Team A wins the race by how many meters?
A. \(40\) meters
B. \((40+10\pi)\) meters
C. \((40+20\pi)\) meters
D. \((20+10\pi)\) meters
E. \((20+20\pi)\) meters
The OA is B
The figure below represents a track with identical
This topic has expert replies
-
- Moderator
- Posts: 2209
- Joined: Sun Oct 15, 2017 1:50 pm
- Followed by:6 members
Timer
00:00
Your Answer
A
B
C
D
E
Global Stats
GMAT/MBA Expert
- Jay@ManhattanReview
- GMAT Instructor
- Posts: 3008
- Joined: Mon Aug 22, 2016 6:19 am
- Location: Grand Central / New York
- Thanked: 470 times
- Followed by:34 members
From the table, we see that Team B finished after 185 - 178 = 7 seconds of Team A. Thus, of the 42 seconds, the 4th runner ran for 42 - 7 = 35 seconds when Team A finished. Thus, Team B lost by the distance that the 4th runner completed in 7 seconds.BTGmoderatorLU wrote:Source: Manhattan Prep
The figure below represents a track with identical semi-circular ends used for a 4-lap relay race involving two 4-person teams (where each team member runs one complete lap around the track). The table below shows the lap times for each runner on Team A and Team B. Assuming that each runner runs at a constant rate, Team A wins the race by how many meters?
A. \(40\) meters
B. \((40+10\pi)\) meters
C. \((40+20\pi)\) meters
D. \((20+10\pi)\) meters
E. \((20+20\pi)\) meters
The OA is B
From the track figure, we know that the two straight lines make up 2*120 = 240 meters. The two identical semi-circular ends make one circle. The radius of the identical semi-circular ends = 1/2 of (180 - 120) = 30 meters. Thus, the length of identical semi-circular ends = 2Ï€*30 = 60Ï€ meters
Length of the track = 240 + 60Ï€
Length of the track yet to be covered by the 4th runner = (7/42)*(240 + 60Ï€) = 40 + 10Ï€ meters
The correct answer: B
Hope this helps!
-Jay
_________________
Manhattan Review GMAT Prep
Locations: Manhattan Review GMAT Prep | Free SAT Practice Questions | LSAT Prep Courses Oxford | SAT Prep Courses Singapore | and many more...
Schedule your free consultation with an experienced GMAT Prep Advisor! Click here.