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GMAT Club World Cup 2026 (Day 7): A weekend training program had 75

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vasu1104

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15 Jul 2026, 00:18

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total people = 75
two tracks = morning and afternoon.

each track has at least 1 person to it.

	mornign	afternoon	T
data			30
no data		x	45
T	75-p	p	75

find. : x/p

S-1

morning data = (2/5) 75-p

but this doesnt give any info to find x or p.
not sufficient.

S-2
afternoon data = (2/3) x
p-x = 2x/3
3p = 5x
p = 5x/3

x / (5x/3) = 3/5

sufficient.

Choice B

Bunuel

A weekend training program had 75 participants, each assigned to exactly one of two tracks: the morning track or the afternoon track, with at least one participant assigned to each track. If 30 of the 75 participants registered for the data-visualization session, what percentage of the afternoon-track participants did not register for the data-visualization session?

(1) Of the morning-track participants, 2/5 registered for the data-visualization session.
(2) Among the afternoon-track participants, the number who registered for the data-visualization session was 2/3 of the number who did not register for it.

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M = number in the morning track
A = number in afternoon track
M+A = 75

30 total registrants so 45 participants did not register

1. 0.4M
morning participants who did not register = M-0.4M = 0.6M
45 participants did not register

45-0.6M
A = 75 - M
sub in the equations 0.6A/A = 3/5 = 60%

Statement 1 is sufficient

Statement 2

R registered
N did not register

R = 2/3N
so the total number is A = R + N = 2/3N + N = 5/3 N

therefoe N/A = N/5/3N = 3?5 = 60%

Statement 2 is sufficient
D each statement alone is sufficient

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St1: As per the attached SS, I assumed the total morning participants as 25x and filled the rest of the table. The question is asking about People in afternoon track who did not register for DV / Total people in afternoon track

As per the SS (Stem + Statement 1 table) this will be (45-15x) / (75-25x) = 15(3-x) / 25(3-x) = 15/25 = 3/5. SUFFICIENT

St2: This statement directly says that if, amongst the afternoon track, the numbet of people who registered for the event was 2, then the number of people who did not register for the event was 3. Hence this makes the total as 5 and the ratio of non registrants to total afternoon track = 3/5. SUFFICIENT

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15 Jul 2026, 01:03

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Question bd
tt participants=75
M+A=75
registered data visualization (dv)=30
did not register for data visualization(Nt)=75-30=45
i need to find the % of afternoon-track participants who did not register= Ant/A*100%
Statement 1
M(dv)=2/5M
since ttl dv=30, Mdv+Adv=30
2/5M+Adv=30
M=75-A
2/5(75-A)+Adv=30
30-2/5A+Adv=30
Adv=2/5A
because A=Adv+Ant, if Adv is 2/5 of A, then Adv must be 3/5 of A
3/5*100%=60% sufficient

Statement 2
among the afternoon-track participants, the number who registered for the data visualization session was 2/3 of the number who did not register for it.
the ratio for afternoon track is:
Adv=2/3Ant
ttl afternoon participants:
A=Adv+Ant=2/3Ant+Ant=5/3Ant
Ant/A= Ant/(5/3)Ant=3/5*100%=60% sufficient
ANS: D. Each statement alone is sufficient.

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15 Jul 2026, 01:14

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Let M=x be morning batch, A=75-x be afternoon batch
Let M_d and A_d be morning and afternoon participants who registered respectively.
Let M_nd and A_nd be morning and afternoon participants who did not register respectively.
We know,
A+M=75
A_d+M_d=30
A_nd+M_nd=75-30=45.
We need to find,
(A_nd/A)*100%.
S1:
M_d=2M/5
So, M_nd=3M/5
therefore, A_nd=45-(3M/5)=3(75-M)/5=3A/5
The answer is 60%
Sufficient

S2:
A_d=(2A_nd/3)
A=A_d+A_nd
A=(5A_nd/3)
The answer is 60%
Sufficient
Therefore, the answer is D

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15 Jul 2026, 01:35

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This question could easily be solved by making a table and putting everything in it like I did.
But before that it would be important to write the given details which could be used with both S1 and S2.

Total 75 participants are there.
Participants are divided into two tracks, I thought of it like a real case scenario, Morning and Afternoon with at least 1 participant in each.
30 out of 75 registered in Data visualization session - and we know it would include both tracks

S1:

The table would be made like this -

Type of track(below)	Data Visual..(DV)	No DV	TOTAL
Morning	2x	3x	5x
Afternoon	(30-2x)	(45-3x)	(75-5x)
Total	30	45	75

Now I will directly divide the number of afternoon-track participants NO DV by total afternoon participants:

(45-3x)/(75-5x)
I checked that we could take 3 and 5 common from numerator and denominator respectively.
[3(15-x)]/[5(15-x)] = 3/5
3/5 is 60%
Sufficient

S2: with similar format I used the same table, I have input given details

	DV	No DV

Afternoon	2y	3y	5y
	30	45	75

It is easier than S1 to prove as 3y/5y would be the percentage that translates to 60%, S2 is also sufficient

ANSWER D

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15 Jul 2026, 01:45

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Total participants = 75
Registered = 30
Not registered = 45

Statement (1): 2/5 of the morning-track participants registered.

Let the number of morning participants be M.
-----> (2/5)M = morning participants who registered.

Since the total number registered is 30,

Afternoon registered = 30 − (2/5)M.

But M is unknown so we cannot determine the number of afternoon participants or the percentage who did not register.

Statement (1) is NOT sufficient.

Statement (2):

A = afternoon participants
R = afternoon participants who registered
N = afternoon participants who did not register

Given: R = (2/3)N

A = R + N
----> (2/3)N + N
----> (5/3)N

Therefore,

N/A = N / [(5/3)N] = 3/5 = 60%

The required percentage is always 60%.

Statement (2) is SUFFICIENT

Answer: B

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15 Jul 2026, 02:03

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total = 75
DV = 30
Not DV = 45
afternoon & Not DV/afternoon = ?

i) let morning = x
DV & morning = (2/5)*x
not sufficient

ii) let Not DV & afternoon = y
DV & afternoon = (2/3)y
total afternoon = (5/3)y
y/(5/3y) = 3/5 = 60% sufficient B

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Information given:

(1) There are 75 people out of which if x people go for morning track, then 75-x go for afternoon track (each participant can go for only 1 track) and x and 75-x are greater than or equal to 1

(2) There are 30 people out of these 75 who register for the DV session.

To find out: What % of 75-x people do not register for DV

Analyzing each statement:

Statement 1: 40% of morning people have registered for DV session.

So, by weighted average concept, if 40% of x have registered and the total %age of people who register for the DV session is also 40%, then the % of people from afternoon track to register for the DV session must also be 40%

Hence, 60% people from afternoon track did not register (we can't find out the absolute numbers because we don't have x but we can find the percentage)

Statement 2: This is more straightforward. We are given the ratio of people who registered for DV vs who did not from the afternoon track people.

Registered = a = 2/3 (not a)

If not a = 3m, then a = 2m , total = 5m

So, not registered = 3m/5m = 60%

Option (D)- Each statement alone is sufficient

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Bunuel

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(1) 30 people signed up for the data visualization program.

Since 2/5 registered from the total number of participants in the morning track, it follows that the number of registered participants in the morning track must be a multiple of 5.

By using the same number of the total 75 participants and those who registered 30 times, only the following combination is possible for the morning and evening track of participants:

Morning: 50 participants, 20 registered

Afternoon: 25 participants, 10 registered

Thus, we find out the nonregistered people in the afternoon: 25 - 10 = 15

Taking into consideration this data, we can calculate: 15/25 = 60% Enough.

(2) As for the afternoon track:

Registered = 2/3 of Not Registered

So, Registered: Not Registered = 2:3

Hence, the fraction of people who did not register equals

3/(2 + 3) = 3/5 = 60%

Thus, we can answer the question directly. Sufficient.

Option D

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15 Jul 2026, 03:01

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The correct answer is D. Each statement is sufficient.

Please check the image for the explanation.

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15 Jul 2026, 03:11

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Given:

	Morning	Afternoon	Total
DV Registered	30-a	a	30
DV Not Registered	45-x+a	x-a	45
Total	75-x	x	75

We need the % of afternoon track participants who did not register : (x-a)/x = 1- a/x

1) 2/5 of the morning track participants registered for data Visualization
As per our table,
-> (30 - a) / (75 - x) = 2/5
-> 5 (30 - a) = 2 (75 - x)
-> 150 - 5a = 150 - 2x
-> 5a = 2x
-> a/x = 2/5
Required % = 1 - (2/5) = 3/5 = 60%
Sufficient

2) Among afternoon participants, DV registered = 2/3 of DV not registered
-> a = 2/3 (x - a)
-> 3a = 2x-2a
-> 5a = 2x
-> a/x = 2/5
Required % = 1- (2/5) = 3/5 = 60%
Sufficient

Ans : D

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15 Jul 2026, 03:15

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Let's make a table for whatever mentioned in the passage.
Morning | Afternoon | Total
Data-Visual. a |. d | 30
No Data-Visual. b |. x. | 45
Total. c |. y. | 75

We need to find: x/y =?

1) this gives 2/5(M) registered of DV.
so the table looks like
M. |A.|T
DV. 2/5*c| d | 30
NDV. 3/5*c| x | 45
T. c. | y | 75

so 3/5*c + x = 45 and c+y =75 if we solve this together then we can get
5x-3y = 0, this will give us x/y = 3/5. SO sufficient.

2) From this we can deduce that d= 2/3*x
so 2/3*x + x = y => this will surely give us a result for x/y. so sufficient.

Answer is D.

Bunuel

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15 Jul 2026, 03:51

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DV = 30/75
% ( AT intersection DV) = ?
(A) MT intersection DV = 2/5
Not sufficient to answer

(B) AT intersection DV = 2/3 (AT intersection not DV)

Sufficient to extract %

(B) is the answer

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15 Jul 2026, 04:07

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1 alone:
m reg = 2/5 of m
let m = x
a reg = 30 − 2x/5, but a total unknown
can't find % not reg
not sufficient

2 alone:
in a, reg : not reg = 2 : 3
so % not reg = 3/(2+3) = 3/5 = 60%
q asks only this %
sufficient
ans: b

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15 Jul 2026, 04:20

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It is given in the question that total participants is 75
30 participants participated in Data- visualisation session

Question - What % of the afternoon track did not participate in data visualisation session

x = Morning participants
y = afternoon participants
x+y = 75

Statement 1 - of the morning participants, 2/5 registered for data visualisation
Hence people who were registered in morning = 2/5 x
Total registered = 30
2/5x + y = 30
y = 30-2/5x

Value of x is not given. Hence this statement is not sufficient

Statement 2 - Among the afternoon participants. registered = 2/3 of those who did not register

Let afternoon not registered be z
afternoon registered = 2/3z
2/3z +z = Total
5/3z = Total
z = 3/5Total

Accordingly, the % who did not register = Number not registered/Total
= (3/5 Total)/Total = 3/5

Hence this statement is sufficient to provide us the answer

Answer is Option B

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15 Jul 2026, 04:43

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Total participants = 75 = MR+MNR+AR+ANR
Registered for data visualisation = 30 =MR+AR
Not registered = MNR+ANR =45
TO FIND: ANR/A *100 =?

1) Of M, 2/5 registered for data visualisation
MR=(2/5)MR+MNR
MR= 2x & MNR=3x
AR=30-2x & ANR=45-3x
ANR/A = (45-3x)/(30-2x+45-3x) =(3/5)100=60 %
It is sufficient

2) AR=(2/3)ANR
AR/ANR=2/3
ANR/A = (3/5)*100=60 %
It is sufficient

D. Each statement alone is sufficient.

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15 Jul 2026, 04:47

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Here's my solution for this question

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15 Jul 2026, 05:41

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It did take time but got the answer.
Solution -
Total - 75 ( also T = M + A) ; Registered - 30 ; M - Morning batch students ; A - Afternoon batch students
Target - Anr( Afternoon batch : non registered)/ A * 100

1 - 2/5*M = Mr (registered for M), Mnr = 3/5*M
M = T - A = 75 - A

2/5*M + Ar = 30 ; Substitute the value of M in this equation
2/5*( 75 - A) + Ar = 30 , on solving we get Ar = 2/5A
Hence Anr = A - Ar = A - 2/5*A = 3/5*A
Target - (3/5A) / A * 100 = 60%
1 is SUFFICIENT

2 -
Ar = 2/3 * Anr
Hence A = Ar + Anr = 2/3*Anr + Anr
Anr = 3/5*A = 60%

2 is sufficient too

Hence Ans - D

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15 Jul 2026, 05:47

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Total participants = 75
Registered =30
Not registered= 45
Morning track= M and Afternoon track=A So M+A=75
Morning registered is MR + AR=30 AR= 30-MR
S1 MR= 2/5M Meaning AR= 30-2/5M but M is unknown factor of 5
If we test cases starting with M=25 we get MR= 10 and AR=20 (Morning not registered is therefore 25-10 =15 while Afternoon not registered is 45-15= 30 so the answer is 30/50x100= 60%.
Trying another case of M=50 yields the same percentage hence S1 is sufficient
S2 If we assume afternoon not registered is x then AR is 2/3x so what the question asks is (x)/(5/3x)
x cancels out leaving 3/5x100=60% hence sufficient
Ans D

Bunuel

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