GMAT Math

DS Question:
On the number line, the distance between point A and point C is 5 and the distance between point B and C is 20. Does point C lie between point A and point B?
1. The distance between point A and point B is 25.
2. Point A lies to the left of B.

PS Question:
A hiker walking at a constant rate of 4 miles per hour is passed by a cyclist traveling in the same direction along the same path at a constant rate of 20 miles per hour. The cyclist stops to wait for the hiker 5 min after passing her, while the hiker continues to walk at her constant rate. How many minutes must the cyclist wait until the hiker catches up?
6 2/3
15
20
25
26 2/3


Thanks in advance....

PS Q:

The hiker travels for (20*5)/60 miles =5/3 miles in 5 min before he waits for the hiker.

The hiker travles (4*5)/60 miles =1/3 miles in the meantime.

So, the cyclist needs to wait until the hiker cover (5/3)-(1/3) miles ie 4/3 miles

To cover this distance the hiker needs, (4/3)* (60/4) =20min

https://goal-mba.blocked

thanks a lot

DS Q:

Here we can see that since A and B are 25 units apart.So C lies between them.

Regarding their position nothing can be inferred from the information provided.

QS Q.

Also here i would like to sujjest that subtracting the speed will directly give u difference in distance.

(20-4) * 5/60 = 4/3 .

Hi,

The way I think of these kind of rates is a little diffrent:
Hiker: Rate 4 miles an hour
Biker: Rate 20 miles per hoer
In 5 minutes the biker covers 5/20 of a mile which is 1/4 of a mile. The hiker walks 5 times slower (20 miles of the biker divided by 4 miles walked by the walker:-)..) so he would need 5*4 minutes

uria wrote:DS Question:
On the number line, the distance between point A and point C is 5 and the distance between point B and C is 20. Does point C lie between point A and point B?
1. The distance between point A and point B is 25.
2. Point A lies to the left of B.

PS Question:
A hiker walking at a constant rate of 4 miles per hour is passed by a cyclist traveling in the same direction along the same path at a constant rate of 20 miles per hour. The cyclist stops to wait for the hiker 5 min after passing her, while the hiker continues to walk at her constant rate. How many minutes must the cyclist wait until the hiker catches up?
6 2/3
15
20
25
26 2/3


Thanks in advance....

My humble answer to you... DS



Sincerely
Alberto Vidal

uria wrote:DS Question:
On the number line, the distance between point A and point C is 5 and the distance between point B and C is 20. Does point C lie between point A and point B?
1. The distance between point A and point B is 25.
2. Point A lies to the left of B.

PS Question:
A hiker walking at a constant rate of 4 miles per hour is passed by a cyclist traveling in the same direction along the same path at a constant rate of 20 miles per hour. The cyclist stops to wait for the hiker 5 min after passing her, while the hiker continues to walk at her constant rate. How many minutes must the cyclist wait until the hiker catches up?
6 2/3
15
20
25
26 2/3


Thanks in advance....

This is my answer to your PS question



Sincerely
Alberto Vidal
the800test.com

Hey Uria.

Consider posting one question per thread, to help keep the discussion as clear as possible.

Both of the problems you submitted are pretty tough, but I hope the videos that show step by step solutions will be helpful.

These are QID 1046 (with correct answer A) and QID 1248 (with correct answer C)

-Patrick

@Patrick_GMATFix,

I have a question regarding the DS question if you dont mind. I understand why A is sufficient, but why isn't B sufficient?

From the given, we can draw the following options:

B--------A-----C---------B

or B------C-------A

Statement B says that A is to the left of B. The only option where A is to the left of B is when C is in the middle, thus sufficient. Or is it that I can't assume that because in drawing 2, C is between B and A; yet A is to the right? Would appreciate your explanation, Thank you!