Train A leaves New York for Boston at 3 PM and travels at the constant speed of 100 mph. An hour later, it passes Train B, which is making the trip from Boston to New York at a constant speed. If Train B left Boston at 3:50 PM and if the combined travel time of the two trains is 2 hours, what time did Train B arrive in New York?
(1) Train B arrived in New York before Train A arrived in Boston.
(2) The distance between New York and Boston is greater than 140 miles.
(A) Statement (1) alone is sufficient, but statement (2) alone is not sufficient.
(B) Statement (2) alone is sufficient, but statement (1) alone is not sufficient.
(C) BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
(D) Each statement ALONE is sufficient.
(E) Statements (1) and (2) TOGETHER are NOT sufficient.
First of all...thanx to prav for a real DS problem...gud!! I wud suggest all of you to try this...this is the toughie level!!
Soln:
without looking at the statements try to solve the problem....
by simple speed distance time equations...you would get a quadratic equation...
Solving you wud get d = 150 miles or 133.33 miles.
that is two probable answers....for these two values you will get two times....
when d =150, Train A 4:30 and train B 4:20
or you could have
when d=133.33 miles, train A 4:20 and train B 4:30....since it is a quadratic expression...
now this is where DS comes in...till here it was a PS.
from statement 1...you could pick one answer....150 miles...and time Train B arrive in New York is 4:20
from statement 2....simply trainB arrives at 4:20
So answer is D....either suffices.
Sorry .. but i can't understand how u arrive on "hen d =150, Train A 4:30 and train B 4:20
or you could have
when d=133.33 miles, train A 4:20 and train B 4:30....since it is a quadratic expression..."???
could u please explain??
I would just add one more possibility to this one,
2(mom/dad)*2(son/mom/dad)*1(only one arrangement to make them sit at the back daughter1-dad/mom/son-daughter2)
So total = 24+4 = 28
not clear.. kindly explain clearly.. thanks!
Should be E
ab = cd = 5 then BC = 10
ab =bc = 9 then CD = 2
How to approach and solve this ?
Point (A,B) is randomly selected inside of circle x^2+y^2=1. What is the probability that A>B>0?
Hmm..would there not be two arrangements to make them sit at the back: daughter1-dad/mom/son-daughter2 and daughter2-dad/mom/son-daughter1.
So, what needs to be added to 24 is 8 (2*2*2) = 32
What do you think?
-------------------------------------------
Thanks,
Ashish
GMAT Faculty @ EducationAisle
GMAT - 99th Percentile, MBA - ISB
Yes....yes.....absolutely ! Missed the trick of shuffling the daughters !
Thanks Ashish !
jamy862004 Saysnot clear.. kindly explain clearly.. thanks!
*2(son/mom/dad)
here, 2 is taken because one of mom/dad will be actually driving, i guess i didnt make it very clear !!
Is this a problem solving question, or a data sufficiency one?
It appears to be a DS type ques, so I'll go woth C ie. both statements are needed.
The second statement confirms that AB is the diameter, and so angle ACB = 90.
Now from statement I and basic trigo, we can find the area (but no need to solve in the context of DS).
Hari Prasad
It needs both A&B; options to solve this.
Sine 30 = 1/Root2= Opposite/Hyp So we can find the value of AC
SImilarly,
Cos 30 = Sqrt3/2 = Adj/Hyp. So we can find value of BC
How to approach and solve this ?
Point (A,B) is randomly selected inside of circle x^2+y^2=1. What is the probability that A>B>0?
x^2+y^2=1, this is a circle with radius = 1 and centered at the origin, if any point is to be randomly selected, for both A&B;>0, just imagine it in the co-ordinate plane.
Points lying in Quadrant 1 will have both ordinate and abscissa +ve, and this is only possible for a qtr of the circle,
Now to get the condition A>B>0, we will have to consider the line x=y, any point lying on the right side of this line, in the first Quadrant will satisfy this condition. How do I know this, cant really explain, it just needs to click !
If you do all this, u will eventually figure out that the portion we are interested in is 1/8th of the Circle !
That is the probability !
If you know your basics, this is actually a 25-30 second question !
A woman is planning a trip that involves 3 connecting trains that depart from Stations X, Y, and Z, respectively. The first train leaves Station X every hour, beginning at 6 a.m., and arrives at Station Y hours later. The second train leaves Station Y every half hour, beginning at 9 a.m., and arrives at Station Z hours later. The third train leaves Station Z every 45 minutes, beginning at 8 a.m. What is the least total amount of time the woman must spend waiting between trains if all trains depart and arrive on schedule, and if she arrives at Station Z no later than 3:30 p.m.?
15 minutes
25 minutes
1 hour 15 minutes
1 hour 40 minutes
4 hours 30 minutes
A woman is planning a trip that involves 3 connecting trains that depart from Stations X, Y, and Z, respectively. The first train leaves Station X every hour, beginning at 6 a.m., and arrives at Station Y hours later. The second train leaves Station Y every half hour, beginning at 9 a.m., and arrives at Station Z hours later. The third train leaves Station Z every 45 minutes, beginning at 8 a.m. What is the least total amount of time the woman must spend waiting between trains if all trains depart and arrive on schedule, and if she arrives at Station Z no later than 3:30 p.m.?
15 minutes
25 minutes
1 hour 15 minutes
1 hour 40 minutes
4 hours 30 minutes
I dont think I understand the question completely because the time reqd to travel between stations has not been provided. If we are to assume any number of hours required, I will blindly mark 0 as the waiting time, but since it is not given as an option, i will go with A)15mins.
To make this possible.....
X->Y (travel from 8am to 9am)
Y->Z (travel from 9am to 10am)
Z-> catch the train at 10:15, so waiting time is 15mins.
Very weird question, with missing info. Please try and check the question before posting !
A Question from the Quant Review Supplement of the OG,2nd Ed
A certain right triangle has sides of length x, y, and z, where x
A.
B.
C.
D.
E.
Can someone help on this one..Question taken from 1000 PS???
10. If A is the center of the circle shown above and AB=BC=CD, what is the value of x?
(A) 15
(B) 30
(C) 45
(D) 60
(E) 75
10. If A is the center of the circle shown above and AB=BC=CD, what is the value of x?
(A) 15
(B) 30
(C) 45
(D) 60
(E) 75
A Question from the Quant Review Supplement of the OG,2nd Ed
A certain right triangle has sides of length x, y, and z, where x
A.
B.
C.
D.
E.
Try lookin at it in terms of co-ordinate axis x-y, with z being the hypotenuse of the right triangle.
z will always be greater than both x and y.
1/2*xy = 1
xy = 2
x = y @ x = y = _/2
Since x
So option A)
rockstarsv SaysCan someone help on this one..Question taken from 1000 PS???
Is it just my browser, or didya not put up an image for the figure there?
Try lookin at it in terms of co-ordinate axis x-y, with z being the hypotenuse of the right triangle.
z will always be greater than both x and y.
1/2*xy = 1
xy = 2
x = y @ x = y = _/2
Since x<_>and the y>_/2
So option A)
Is it just my browser, or didya not put up an image for the figure there?
Very nicely done Angad bhai !
When r u planning to give ur GMAT?
And yes, the figure in that question by rockstar is invisible
Very nicely done Angad bhai !
When r u planning to give ur GMAT?
And yes, the figure in that question by rockstar is invisible
Thank you hai sausi bhai. GMAT yar, once i start getting consistent 720+ atleast in the mocks, i'll go ahead and book the slot right away. Although I'm planning within 2-3 weeks. Abhi mamla thoda damadol hai :D. And what about you??
If x is positive which of the following could be correct ordering of 1/x, 2x, x^2.
1) x^2
2) x^2
3) 2x
Options:
1) None
2) 1 Only
3) 3 Only
4) I and 2 only
5) 1, 2, 3
If x is positive which of the following could be correct ordering of 1/x, 2x, x^2.
1) x^2
2) x^2
3) 2x
Options:
1) None
2) 1 Only
3) 3 Only
4) I and 2 only
5) 1, 2, 3
The Answer must be 3 only. I stand to be corrected though.
If x is positive which of the following could be correct ordering of 1/x, 2x, x^2.
1) x^2
2) x^2
3) 2x
Options:
1) None
2) 1 Only
3) 3 Only
4) I and 2 only
5) 1, 2, 3
The Answer must be 3 only. I stand to be corrected though.
I am sorry to differ but I think it's option 2: 1 only...
Thank you hai sausi bhai. GMAT yar, once i start getting consistent 720+ atleast in the mocks, i'll go ahead and book the slot right away. Although I'm planning within 2-3 weeks. Abhi mamla thoda damadol hai :D. And what about you??
If x is positive which of the following could be correct ordering of 1/x, 2x, x^2.
1) x^2
2) x^2
3) 2x
Options:
1) None
2) 1 Only
3) 3 Only
4) I and 2 only
5) 1, 2, 3
Damadol to mera bhi chal raha hai 😞 But my date is on 6th Sept, keeping my fingers crossed.....
I will go with 4) for this one.....
plug in 1/2, 1 is possible
plug in 0.9, 2 is possible....
3) is not possible with any value, i guess.....
Arithmetic approach, anyone?
Damadol to mera bhi chal raha hai 😞 But my date is on 6th Sept, keeping my fingers crossed.....
I will go with 4) for this one.....
plug in 1/2, 1 is possible
plug in 0.9, 2 is possible....
3) is not possible with any value, i guess.....
Arithmetic approach, anyone?
ya got it.....option 4
Damadol to mera bhi chal raha hai 😞 But my date is on 6th Sept, keeping my fingers crossed.....
I will go with 4) for this one.....
plug in 1/2, 1 is possible
plug in 0.9, 2 is possible....
3) is not possible with any value, i guess.....
Arithmetic approach, anyone?
vjjani Saysya got it.....option 4
Option 4 is correct!