[Nikolai]

I'm going with (b) 13, and heres why

simple method, zero confusion:
draw a 7x7 grid, the top 7 indices standing for days of the week starting from the first day (1) and the vertical indices being the week numbers. in cell 1x1, put N, D and M in it together and strikeout. every two cells, mark it N standing for the days on which Nishant went jogging.

all along column one, mark it M for days on which Mohit went jogging and strikeout the cell when M coincides with N. Now you have days on which M and N went jogging alone.

Now start striking out every second N cell starting with cell 1x1 to account for all the days D went jogging with N.

We see that

Week---People Jogging Alone
1 ----------- 2
2 ----------- 2
3 ----------- 1
4 ----------- 3
5 ----------- 2
6 ----------- 2
7 ----------- 1

Total people jogging alone = 13

Hope this was helpful

[vickykansal]

Originally Posted by getneonow

Firstly from question i m clear that we have to calculate for only 7 weeks(starting from first day) i.e 49 days.

I m listing out the days they wud go alone
Nishant -- 2,6,12,18,22,26,30,34,38,46 ==>count = 10
Deepak -- none
Mohit -- 7,21,35,49 ==>count =4

So ans is 10+4 = 14 (c)

Neo

Hey Dont you think it should be
Nishant 1,3,5,7,9...etc

I mean he started today so why not count 1??

[Destiny's_Child]

My answer is 14

For mohit: there would be four days when he would be alone.

For nishant : there would be 10 days when he would be alone(odd multiples of 2 - odd multiples of 2 which are multiple of 7 as well)

For Deepak : he would never go alone, he would always be accompanied by nishant.

So total number of days = 10 + 4 = 14 Ans

[bijudas100]

Originally Posted by vivekr

The question says.. "If its the first day that they started this routine, what is the total number of days that each person will jog by himself in the next seven weeks?"

I think this means a total of 50 days (1+49), which'd lead to an answer of 14 (10+4).

I too got the answer as 13 first . But seems like this is a valid point . So shall we take it as 49 days or 50 days ?

[vickykansal]

Originally Posted by bijudas100

I too got the answer as 13 first . But seems like this is a valid point . So shall we take it as 49 days or 50 days ?

hmmm if we go purely by the words in the question it means the next 49 days... i.e 7 weeks after today... so the number of day should be 49 only but it should start from the nextday, not including today. Am i making sense??

[MBA_007]

hi all

if they started on day 1
then
Nishant jogged on day 1,3,5,7,9---------------49
dipak jogged on day 1,5,9,13-----------49
mohit jogged on days 1,8,15,22,29,36,43

in all they have jogged for 28 days
out of which first two have jogged together for 13 days
while 1 and 3 have jogged together(excluding common to second one) for 2 days

so total days for which they jogged alone are 28-2-13 =13 days

ans 13 days

[vineet.nitd]

Originally Posted by bijudas100

I too got the answer as 13 first . But seems like this is a valid point . So shall we take it as 49 days or 50 days ?

It means total 49 days only . The language of this problem says that "Its the first day " and the next 7 weeks includes the same .

Week here means Sunday to Saturaday . Consider the first day as Sunday .

[vivekr]

Originally Posted by vineet.nitd

It means total 49 days only . The language of this problem says that "Its the first day " and the next 7 weeks includes the same .

Week here means Sunday to Saturaday . Consider the first day as Sunday .

Then the answer must be 13 days (10 + 3)

[Nikolai]

Purely on the basis of the words in the question, it means a total of 49 days, including the first day - not 1+49...

Remember, the question says 'first day', not 'one day'... 'first day' in this case HAS TO apply to some sort of series of days; hence, in the next 7 weeks, would come to be read as the 49 days inclusive of that day.

If the question read as 'the next 7 weeks following that day', that would be a specification of 1+49

I hope my logic is universally appealing.

[vineet.nitd]

Originally Posted by vivekr

Then the answer must be 13 days (10 + 3)

Yup answer is 13 =(10+0+3)