BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

Writing Speed(plz explain)

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Senior | Next Rank: 100 Posts
Posts: 38
Joined: Sun Feb 14, 2010 8:53 am

Writing Speed(plz explain)

by akpareek » Fri Apr 09, 2010 8:06 am
Two boys begin together to write out a booklet containing 535 lines. the first boy starts with the first line, writing at the rate of 100 lines per hour; and the second starts with the last line then writes line 534 and so on, backward proceeding at the rate of 50 lines per hour. At what line will they meet.

A. 356
B. 357
C. 277
D. 267
E. 257
Top
Source: — Problem Solving |
Master | Next Rank: 500 Posts
Posts: 216
Joined: Mon Dec 21, 2009 10:26 am
Thanked: 16 times

by student22 » Fri Apr 09, 2010 9:35 am
This is a variation of the two airplanes flying at each other problem.

Here's how to solve it, add the two rates together, 100 + 50 = 150.

Now use the rate formula of r * t = d

So set the rate equal the total amount (or distance): 150t = 535 ---> t = 3.566667.

That means that they will meet in 3.5666667 hours, so simply plug that time back into one of the two rates to see what page they will meet at:

100 (3.56) = 356.

or

100 (3.57) = 357.

I'm really not sure how it wants you to round this problem. I've never seen an official GMAT problem this ambiguous. But it's either A or B. Similar problems that I've seen always divide cleanly or at least have terminating decimals (i.e. 3.25)
Top
Senior | Next Rank: 100 Posts
Posts: 51
Joined: Mon Jul 13, 2009 4:25 pm
Thanked: 1 times

by ymach3 » Sat Apr 10, 2010 12:01 am
100 t =535

50t=535-x

When solved, we get x =535-267.5=267 lines.

Option-D

Did i mess it up somewhere ??
Top
Master | Next Rank: 500 Posts
Posts: 268
Joined: Wed Mar 17, 2010 2:32 am
Thanked: 17 times

by this_time_i_will » Sat Apr 10, 2010 12:45 am
akpareek wrote:Two boys begin together to write out a booklet containing 535 lines. the first boy starts with the first line, writing at the rate of 100 lines per hour; and the second starts with the last line then writes line 534 and so on, backward proceeding at the rate of 50 lines per hour. At what line will they meet.

A. 356
B. 357
C. 277
D. 267
E. 257
The easiest way to solve this and other similar questions is to use relative speed concept of Time & Distance type problems.
Let the distance = 535 lines.
relative speed = 100+50 = 150 lph.
so both meet at = 535/150 = 3.566 hrs

So, in 3.566 hrs, first boy would have reached at line number = 3.566*100 = 356.6 .
= this means the first boy would be writing 357th line.
Top
Master | Next Rank: 500 Posts
Posts: 148
Joined: Tue Jun 09, 2009 11:06 pm
Thanked: 7 times

by pops » Sat Apr 10, 2010 12:49 am
ymach3 wrote:100 t =535

50t=535-x

When solved, we get x =535-267.5=267 lines.

Option-D

Did i mess it up somewhere ??
aye, 100t = x (and not 535, accroding to you A is writing all the 535 lines)
Top
Senior | Next Rank: 100 Posts
Posts: 38
Joined: Sun Feb 14, 2010 8:53 am

by akpareek » Sat Apr 10, 2010 10:06 am
Thanks Guys !!!!!!!
Top
Post new topic Post Reply
• Page 1 of 1