GRE Prep Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized
for You
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Running on a 10-mile loop in the same direction, Sue ran at
[#permalink]
14 Jun 2018, 14:39
14 Jun 2018, 14:39
Expert Reply
4
Bookmarks
00:00
Question Stats:
73% (01:18) correct
26% (01:19) wrong based on 84 sessions
Hide Show timer Statistics
Running on a 10-mile loop in the same direction, Sue ran at a constant rate of 8 miles per hour and Rob ran at a constant rate of 6 miles per hour. If they began running at the same point on the loop, how many hours later did Sue complete exactly 1 more lap than Rob?
(A) 3
(B) 4
(C) 5
(D) 6
(E) 7
(A) 3
(B) 4
(C) 5
(D) 6
(E) 7
Re: Running on a 10-mile loop in the same direction, Sue ran at
[#permalink]
07 Jul 2018, 04:28
07 Jul 2018, 04:28
1
Expert Reply
Explanation
If Sue completed exactly one more lap than Rob, she ran 10 more miles than Rob. If Rob ran d miles, then Sue ran d + 10 miles. Rob and Sue began running at the same time, so they ran for the same amount of time. Let t represent the time they spent running. Fill out a chart for Rob and Sue, using the formula Distance = Rate × Time (D = RT):
There are two equations:
\(d = 6t d + 10 = 8t\)
Substitute 6t for d in the second equation and then solve for t:
\(6t + 10 = 8t\)
\(10 = 2t\)
\(5 = t\)
Hence option C is correct!
If Sue completed exactly one more lap than Rob, she ran 10 more miles than Rob. If Rob ran d miles, then Sue ran d + 10 miles. Rob and Sue began running at the same time, so they ran for the same amount of time. Let t represent the time they spent running. Fill out a chart for Rob and Sue, using the formula Distance = Rate × Time (D = RT):
| D(miles) | = | R(miles per hour) | \(\times\) | T (hours) | |
| Rob | d | = | 6 | \(\times\) | t |
| Sue | d+10 | = | 8 | \(\times\) | t |
There are two equations:
\(d = 6t d + 10 = 8t\)
Substitute 6t for d in the second equation and then solve for t:
\(6t + 10 = 8t\)
\(10 = 2t\)
\(5 = t\)
Hence option C is correct!
Re: Running on a 10-mile loop in the same direction, Sue ran at
[#permalink]
04 Nov 2018, 08:11
04 Nov 2018, 08:11
2
Difference in distance/Difference in speeds = 10/(8-6) = 5
