John works five days each week except when on the vacation or during

Conclusion:Therefore, he must have worked in the
insurance company on Monday, Tuesday, Wednesday,
and Thursday last week.
Premise:Four days a week he works in an insurance
company; on Fridays he works as a blacksmith. Last
week there were no holidays, and John was not on
vacation
Possible Assumption: As conclusion says he worked on M,T,W,T and F as a Blacksmith. at the same time, as we know he works only 5 days a week. So from the above data it is clear that he didn't worked on Sat and Sun.

POE:
a)Incorrect John never takes a vacation of more than one week in length.
Not relevent to the present context.
b)Incorrect Every day last week that John worked, he
worked for an entire workday.
It doesn't link premise to the conclusion. Whether he works for full day or not it does't matter because we are concerned with only days in which he worked for last week.
So this one is also irrelevant.
C) IncorrectJohn does not take vacations in weeks in which
national holidays occur.
Not relevant.
d) CorrectLast week John worked neither on Saturday
nor on Sunday.
It matches with our thinking
Just recheck through "Negation test"
On negating we get " Last week John worked on Saturday
and on Sunday". this negated option tears our conclusion.
e)Incorrect There were no days last week on which John
both worked in the insurance company and
also worked as a blacksmith.
It has no relavence to the stimulus

It helps me to visualize the things

John's normal routine is -

Further it is stated -

So,Be what John worked for 5 days last week...

Now, from this data the Author concludes that John worked at the Insurance Company as per his usual routine ( without any exception ), that might be possible only if

He works as per routine and doesn't substitute the usual work days for a Saturday / Sunday...

If John decides to make weekly of or takes 2 days leave with the condition that he will have to go to office on Saturday/ Sunday, then the conclusion doesn't hold true..

Hence , answer must be (D)

Clear D.

E - cannot be assumption. If it were an assumption, then total number of days worked last week will be 4 (3 days(insurance) + Friday(insurance + blacksmith)), which contradicts the premise - john works 5 days a week unless that week has national holiday or he is on vacation.

Fairly straight forward question. Answer, D.

a) John never takes a vacation of more than one week in length. - We don't care about how long his vacations are. The question talks about his schedule last week and we know he wasn't on vacation then. So out.

b) Every day last week that John worked, he worked for an entire workday. - Out of scope. Even on normal days we don't know if he works full-time or part-time, so negating this would in no way change the conclusion

C) John does not take vacations in weeks in which national holidays occur. Out of scope. Even if he does take vacations in weeks with holidays, the argument states that last week there were no holidays nor was he on a vacation. We are only concerned about last week

d) Last week John worked neither on Saturday nor on Sunday. Correct. If we negate this, it means John worked on Saturday or/and Sunday at the insurance company. But since he only works four days at the insurance company, he could not have worked there Mon-Thurs.

e) There were no days last week on which John both worked in the insurance company and also worked as a blacksmith. If we take this to be true, it still leaves the possibility open that he worked on Saturday or/and Sunday. Therefore, he could not have worked Mon-thursday. Incorrect.

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