Tricky ones

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Tricky ones

by raju232007 » Mon Feb 08, 2010 7:46 am
1.Two typists Mia and Gerard work alternatively on a typewriter, one hour at a time. How many hours do they take to type a report?

1. Mia alone takes 10 hours to type the entire report.
2.Gerard alone takes 14 hours to type the entire report.

OA is E

2. If a,b and c take distinct integer values from '0' to '9', is a+b+c a multiple of 9?

1. (a*b) + c is a multiple of 9
2. (a+b)*c is a multiple of 9

OA is E

I would certainly appreciate if you can provide detailed explanation for these problems....Thanks
Source: — Data Sufficiency |

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by bhumika.k.shah » Mon Feb 08, 2010 7:47 am
Request - please post one question in one new topic.

This gets too cumbersome

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by bhumika.k.shah » Mon Feb 08, 2010 7:49 am
raju232007 wrote:1.Two typists Mia and Gerard work alternatively on a typewriter, one hour at a time. How many hours do they take to type a report?

1. Mia alone takes 10 hours to type the entire report.
2.Gerard alone takes 14 hours to type the entire report.

OA is E


According to me its E because we dont know how long is the report .

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by thephoenix » Mon Feb 08, 2010 10:27 am
raju232007 wrote:1.Two typists Mia and Gerard work alternatively on a typewriter, one hour at a time. How many hours do they take to type a report?

1. Mia alone takes 10 hours to type the entire report.
2.Gerard alone takes 14 hours to type the entire report.

OA is E
its E bcoz we are not sure for the report asked in Q and data given in statemnts are for the same one

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by thephoenix » Mon Feb 08, 2010 10:37 am
raju232007 wrote: 2. If a,b and c take distinct integer values from '0' to '9', is a+b+c a multiple of 9?

1. (a*b) + c is a multiple of 9
2. (a+b)*c is a multiple of 9

OA is E

I would certainly appreciate if you can provide detailed explanation for these problems....Thanks
for q like this pick some values

s1) if a=0 then irrespective of any value of b c has to be 9 to satisfy the condition of s1) but a+b+c is not div by 9
now to prove it div by 9 is rather much easy let a=6 b=3 and c=9
then ab+c is div by 9 and
a+b+c is also div by 9
hence insuff
s2)
for a=1;b=2;c=3
cond 2 is met and a+b+c is div by 9

for a=2 b=4 and c= 3
cond of s2 is met but a+b+c is not div by 9
hence insuff

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by raisethebar » Tue Feb 09, 2010 1:55 am
bhumika.k.shah wrote:
raju232007 wrote:1.Two typists Mia and Gerard work alternatively on a typewriter, one hour at a time. How many hours do they take to type a report?

1. Mia alone takes 10 hours to type the entire report.
2.Gerard alone takes 14 hours to type the entire report.

OA is E


According to me its E because we dont know how long is the report .
:) I dont think that the resoning is correct.
please correct if I am wrong ans is E bcause who first started the work(Mia or Gerand) is not given. The answer varies depending on who states first.

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by raisethebar » Tue Feb 09, 2010 1:58 am
thephoenix wrote:
raju232007 wrote:1.Two typists Mia and Gerard work alternatively on a typewriter, one hour at a time. How many hours do they take to type a report?

1. Mia alone takes 10 hours to type the entire report.
2.Gerard alone takes 14 hours to type the entire report.

OA is E
its E bcoz we are not sure for the report asked in Q and data given in statemnts are for the same one
That's the great guess but i dont think that is the reason.

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by raisethebar » Tue Feb 09, 2010 2:05 am
thephoenix wrote:
raju232007 wrote:1.Two typists Mia and Gerard work alternatively on a typewriter, one hour at a time. How many hours do they take to type a report?

1. Mia alone takes 10 hours to type the entire report.
2.Gerard alone takes 14 hours to type the entire report.

OA is E
its E bcoz we are not sure for the report asked in Q and data given in statemnts are for the same one
That's the great guess but i dont think that is the reason.