In Area X, for three continuous days in a certain month of 2012, five

Question

In Area X, for three continuous days in a certain month of 2012, five planets - Jupiter, Mercury, Mars, Saturn, and Venus - were all visible on the same day after dusk. Such an event only occurred once that year. Venus was visible on every day in April and May; Jupiter was visible on every day in April and on two days in May. Did the event occur in the period comprising April and May?

(1) In April in Area X, Jupiter and Venus were visible between dusk and midnight.
(2) In Area X, Mercury, Mars, and Saturn were all visible on the same day after dusk for three continuous days that were not in May.

Bunuel · Accepted Answer

In Area X, for three continuous days in a certain month of 2012, five planets - Jupiter, Mercury, Mars, Saturn, and Venus - were all visible on the same day after dusk. Such an event only occurred once that year. Venus was visible on every day in April and May; Jupiter was visible on every day in April and on two days in May. Did the event occur in the period comprising April and May?

So the question is simply asking: Did the 3 consecutive day five planet visibility event happen at some point during April or May?

It does not mean it has to span both months. It would count as “yes” even if all 3 days were in April, or all 3 days were in May, or it crossed from late April into early May.

(1) In April in Area X, Jupiter and Venus were visible between dusk and midnight.

In April, we already know Jupiter and Venus are visible every day after dusk. This statement adds a time window, but it gives no information about Mercury, Mars, and Saturn lining up for three straight days in April. Not sufficient.

(2) In Area X, Mercury, Mars, and Saturn were all visible on the same day after dusk for three continuous days that were not in May.

This says Mercury, Mars, and Saturn line up for three consecutive days, and that stretch is not in May. The five planet event cannot be in May anyway (Jupiter is visible only two days in May, so it cannot be part of a three day consecutive event within May). But the three day Mercury-Mars-Saturn stretch could be in April (then the answer is yes, because Jupiter and Venus are visible every day in April) or it could be in some other month (then the answer could be no). Not sufficient.

(1)+(2) Still does not tell whether that three day Mercury Mars Saturn stretch is in April. Not sufficient.

Answer: E.

gemministorm · Answer

- Given facts:
- Venus: visible every day in April and May.
- Jupiter: visible every day in April and on two days in May.
- The five-planet event happened exactly once in 2012.
- The event requires “visible after dusk,” not just general visibility.

(1) In April in Area X, Jupiter and Venus were visible between dusk and midnight.
- only a timing qualification for Jupiter and Venus in April (after dusk, up to midnight).
- It says nothing about Mercury, Mars, or Saturn in April.
- Without those three, we cannot confirm the five-planet event occurred in April or May.
Conclusion: Statement (1) alone is not sufficient.

(2) Mercury, Mars, and Saturn were all visible on the same day after dusk for three continuous days that were not in May.
- This guarantees the “triple” (Mercury–Mars–Saturn) for three consecutive days outside May.
- Those three days could be in April, or in any other month (e.g., June).
- If they happened in April, then Venus and Jupiter were visible in April (from the prompt), potentially satisfying the five-planet condition; if they happened in another month, Venus/Jupiter visibility is unknown and the event may not occur then.
Conclusion: Statement (2) alone is not sufficient.

Combining statements (1) and (2)
- If the triple occurred in April:
- From (1), Jupiter and Venus were visible after dusk in April.
- From (2), Mercury, Mars, and Saturn were visible after dusk for three consecutive days (not in May), which could be April.
- Thus, the event could have occurred in April, giving a “Yes.”
- If the triple occurred in a different month (not May):
- (1) says nothing about any month other than April.
- we cannot assert Venus or Jupiter were visible after dusk in that other month.
- The event could fail to occur there, giving a “No.”
Because the triple’s three-day run could be either in April (Yes) or in another month (No), even together the statements don’t pin down whether the unique event happened within April–May.
hence: E (Statements (1) and (2) together are not sufficient)

ritik0212 · Answer

- Did the event occur in the period comprising April and May?
I though the statement meant that it should both months. like anytime between (28th apr to 1st May) - (30th apr to 2nd may)
so 2nd statement seemed enough to answer.

gemministorm · Answer

according to 2nd statement:
- Those three days could be in April, or in any other month (e.g., June). 
 - If they happened in April, then Venus and Jupiter were visible in April (from the prompt), potentially satisfying the five-planet condition; - YES
if they happened in another month, Venus/Jupiter visibility is unknown and the event may not occur then. - NO

so 2 alone is not sufficient.

Ishita123457 · Answer

Shouldn't statement 2 be enough? Since the question asks, 'Did the event occur in the period comprising April and May?' Since we know for sure from statement 2 that it did NOT occur in May?

Bunuel · Answer

“Did the event occur in the period comprising April and May?” means: did the 3 day event happen at any time during the two month window April 1 through May 31? So it counts as Yes if the 3 days are in April, or in May, or even if the 3 days cross from late April into early May.

(2) only says the 3 day stretch was not in May. That still leaves two possibilities: it happened in April (then the answer is Yes) or it happened in some other month (then the answer is No). So statement (2) is not enough.

vpt2021 · Answer

I think a critical point we all missed here is in the pre-thinking: just because Venus and Jupiter are visible in April and May does not necessarily mean they were visible only in those months.

RJ3001274402 · Answer

Statements (1) + (2)
From (2): the 3-day window is not in May.
From (1): April has Jupiter and Venus visible after dusk.
However, nothing guarantees that:
Jupiter was visible on those same 3 days as Mercury, Mars, and Saturn.
The 3-day Mercury–Mars–Saturn overlap could occur:
in April on days when Jupiter is not visible after dusk, or
in some other month entirely.
Both answers (Yes or No) are still possible.
❌ Still insufficient

eaat · Answer

For this question, both aren't sufficient, right, because we're not told that they were only visible on these days in April or May, so it could have been any other month, like February, for example 
@bunel

Bunuel · Answer

Correct. Even with both statements, we do not know whether the three continuous days for Mercury, Mars, and Saturn were in April or in some other month.

If they were in April, the answer would be yes. If they were in February, the answer could be no. So the statements together are not sufficient.

Amity007 · Answer

Bunuel , I had only one query about this answer.

It has mentioned in the question that, these 3 days where all the planets were visible occurred exactly once that year.
And since, jupiter was seen only april and 2 days in may. then there wouldn't be any other month apart from April/may where all 5 planets can be visible.
Rest after adding statement 2 to it, it helps to add that yes it would have occurred in April only as it didn't happen in may for sure. So statement 2 might be sufficient enough.

Can you please correct my reasoning if i'm assuming anything here?

Bunuel · Answer

The mistake is assuming Jupiter was visible  only  in April and on two days in May. The stem does not say that, so the event could have occurred in another month.

egmat · Answer

Hi Amity007,

Your logic is airtight  given one assumption , and that assumption is exactly the thing to check. You wrote that "Jupiter was seen only in April and 2 days in May." Read the stimulus again carefully:

"Venus was visible on every day in April and May; Jupiter was visible on every day in April and on two days in May."

This tells you Jupiter and Venus  were  visible on those days - it never says those were the  only  days they were visible. Jupiter could easily have been visible in February, June, or any other month too; we simply aren't told. So the hidden constraint you're leaning on - "the five-planet event can  only  physically happen in April/May" - isn't actually stated.

Once that constraint is gone, Statement ( 2 ) stops being enough. It says Mercury, Mars, and Saturn lined up for three continuous days  not in May . Those three days could land in April  or  in some entirely different month.

Two cases that both satisfy Statement (2):

- The three days are in  April . Venus and Jupiter are visible all April, so all five coincide - event is in April -  YES .
- The three days are in  February . Nothing rules out Venus and Jupiter also being visible then, so all five could coincide in February - event is  not  in April/May -  NO .

Same statement, two different answers -  not sufficient . And notice this is exactly why the combination fails too: Statement ( 1 ) only pins down Venus/Jupiter  in April , so it can't force those three overlap days into April.

The takeaway:  in DS, only use constraints the text actually gives you. "Was visible in April and May" is not the same as "was visible only in April and May" - and that one word gap is what flips this from a clean C/B to  E .

Answer: E

In Area X, for three continuous days in a certain month of 2012, five

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GMAT Data Sufficiency (DS) Questions

In Area X, for three continuous days in a certain month of 2012, five

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