Data Sufficiency

check .jpg

OA------------------------------D

source-OG 11/12

is the answer D?

nitya34 wrote:check .jpg

if at most 6 people have their birthday on any month and there are 66 total in the auditorium, then 11 months are accounted for and there doesn't have to be at least one person in one month.

statement 1)
Feb>March means that the 6 necessary for each month to have 1 month with no birthdays gets disrupted. Because march would have to have at least 5 birthdays.

sufficient

statement 2)

same as s1. once you drop below six to five, then in every month at least one person has a birthday.

you got this!

sd

I know this is an old topic at this point. But I came across this question recently while studying and no one appears to have addressed my logical conundrum.

1) Sufficient. If the distribution among months is uneven, there must be one at least one birthday in every month within the group.

2) If 5 of the people have birthdays in March (if M = number of birthdays in March) then M > 5 but also less than or equal to 6. The way I read this statement it gives you information for 5 people, however the remaining 61 people are unknown. Of the remaining 61, one other can also have a birthday in March making it possible that January birthdays are not represented. Insufficient.

I don't know if my studying for CR is messing up my reasoning for DS, but this was the way I read the question and got it incorrect. I thought that as a result, this question was poorly written, however it is an OG question therefore it must be something to expect on the test. Should I change my thinking on the Math section? Particularly the DS?

(Expert replies/advice welcomed!)

nitya34 wrote:check .jpg

OA------------------------------D

source-OG 11/12

There are 66 people and at most 6 people may have their birthdays in a given month. In order to answer the target question, we'll have to address the worst case scenario, if we can know some more about it.

(1) The worst case scenario here is that there are 6 people having their birthdays in February and 5 people having their birthdays in March. Keeping January aside, if each of the remaining 9 months have 6 people having their birthdays the same month, we meet a total of 6 + 5 + 9 (6) = 65 people who can be allotted to the 11 months other than January, which leaves at least 1 person having their birthday in January. [spoiler]YES! Sufficient[/spoiler]

(2) Here again, the worst case scenario is that, keeping January aside, given 5 people have their birthdays in March, we can assign each of the remaining 10 months have 6 people having their birthdays the same month, thus we meet a total of 5 + 10 (6) = 65 people who can be allotted to the 11 months other than January, which leaves at least 1 person having their birthday in January. [spoiler]YES! Sufficient


Pick D[/spoiler]