Practice Questions Chat

PS Question 1 - Apr 30

In a 3600 m race around a circular track of length 400m, the faster runner and the slowest runner meet at the end of the fourth minute, for the first time after the start of the race. All the runners maintain uniform speed throughout the race. If the faster runner runs at thrice the speed of the slowest runner. Find the time taken by the faster runner to finish the race.

A. 36 minute
B. 24 minute
C. 16 minute
D. 12 minute
E. 10 minute

Source: Others | Difficulty: Hard

DS Question 1 - Apr 30

If |x² + 3x – 7| = 3, is x prime?

1. x² > 9
2. 3x ≤ 12

Source: Princeton Review | Difficulty: Hard

DS Question 2 - Apr 30

If p is a positive integer, what is the remainder when p^2 – 1 is divided by 8?

(1) p is completely divisible by 3
(2) p leaves a remainder when divided by 2.

Source: GMATWhiz | Difficulty: Hard

Hello, do I require to study parabola topic for gmat ?

Is there a way I can post doubts here on GMAT Club?
Where can I do that

Thanks

Quadratic equations are asked in GMAT Quant. You may not expect complex graph based questions using parabola.

There are couple of ways - 1) You can post your question in the discussion thread if there exists one. If not, you can create one by yourself. 2) You can post quant questions / queries on this chat group and verbal ones in the verbal chat group. 3) If you have a specific query on a topic, you can always create a post and tag an expert for their response.




DS Question 1 - May 01

If p and q are positive integers such that p = 4q – 3, what is the greatest common divisor of p and q?
(1) q = 3k, where k is an integer
(2) p = 3m, where m is an integer

Source: GMATWhiz | Difficulty: Hard

PS Question 1 - May 01

A shipment of 500 bulbs contains 10% defective bulbs. If three bulbs are chosen randomly, what is the probability that exactly 2 of them are defective?

A) 1/500

B) 3/500

C) 3/1000

D) 9/1000

E) 27/1000

Source: Expert’s Global | Difficulty: Hard

I didn’t find any precise answer. Closest I could get is 27/1000.
Solution:
50 Defective; 450 Good
50C2*450C1 / 500C3 = 49*45*3 / 499*498 = 27*245 / 499*498 = 27/499*2.03 = 27/1012

D; pairs possible 1,1; 5,2; 9,3; 13,4; 17,5; 21,6.....33,9....
wherever, P or Q are multiple of 3, HCF/GCD is 3

"Chosen randomly" - does this mean that the bulbs are not picked? In other words bulb is selected and placed back before next selection?
In such case, we can use faulty coin toss concept-
3C2 * (0.1)(0.1)(0.9) = 27/1000
This is not entirely clear, don’t know how do we differentiate between the two.

DS Question 1 - May 02

If x and y are integers, is x = y ?

(1) x! = y!
(2) x^y = x

Source: Other | Difficulty: Medium

PS Question 1 - May 02

If the sum of the first 30 positive odd integers is k, what is the sum of first 30 non-negative even integers?

A. k-29
B. k-30
C. k
D. k+29
E. k+30

Source: eGMAT | Difficulty: Hard

E

sum of first 30 odd int = k = 900 and sum of first 30 non negative even int = 870 = k-30 ... "option B"

E; both equations work for x=1 & y=0 or 1

B; K-30

A

And is 26.46/1000 which is closest to 27/1000 I.e E

Answer is D for this

A lil off the context, but is anybody here taking any kind of profile building assistance and applications drafting help?
Need recommendations
Thanks

Andy is planning to go from A to B. He needs to reach B for an important meeting scheduled. He must be on time. After travelling for some time he realises that he will cover only 2/3 rd of the distance by the time the meeting starts. Hence, he increases speed to 2.5 times his initial speed. Thus he manages to be exactly on time. If he had not changed his speed he would have been 4 hrs late for the meeting. After travelling for how many hours did Andy change his speed.? Need solution pls

Can you please share the complete question (along with the options)

Ans - 16/3 hrs? (I’m half asleep, silly mistake alert )
Solution -
We need to consider 2 splits for the route. Call distance "x"
1) x= 2/3 & 1/3 ; as per hypothetical condition
2) t= t1 + t2 ; actual situation
also, 2.1) x = vt1 +5v/2 * t2 ; actual situation
Case 1: 2x/3 = vt and x = v(t+4); hence, t=8
( So, by 2)) t1+t2=8; ---- EQ1
(by 2.1) vt1+5v/2 * t2 = v(t+4)
hence, 2t1+5t2=2t+8=24 -------- EQ2
solve 2 equations t1 = 16/3; t2=8/3

PS Question 1 - May 3

Jorge’s bank statement showed a balance that was $0.54 greater than what his records showed. He discovered that he had written a check for $x.yz and had recorded it as $x.zy, where each of x, y, and z represents a digit from 0 though 9. Which of the following could be the value of z ?

A. 2
B. 3
C. 4
D. 5
E. 6

Source: Official Guide | Difficulty: Hard

DS Question 1 - May 3

Is x+y–z+t even?

(1) x+y+t is even
(2) t∗z is odd

Source: Others | Difficulty: Hard