LCM

[shivani_bha]

Hi Testmagicians,

Can't seem to solve this.

When I met a friend today we observed that my birthday is x months away,
while his birthday is y months away. The difference between our ages in
less than a year. Also we observed that the difference of our ages in
months is the LCM of x and y. Which of the following can be the difference
of our ages.

1) 4 months 2) 6 months 3) 8 months 4) 10 months

Any 2 nos that are co-primes of each other will give an LCM of greater than 12 (eg 7 and 3) while any no that is a multiple of the other no will give the greater no as LCM (therefore this cannot be the no)

Any ideas on how to solve this?

Thanks
Shivani

[gmatfordays]

Hi Shivani,

What source did you get this question from.. I too cannot find a number that will work (nor an equation to support this) LCM of xy = (diff of x and y) where the diff of x and y < 12. If the question said the diff was less than or = to 12 , then answer 2) 6 months would be correct. However, I am not able to find anything else.

Totally stumped....[bomb]

[shivani_bha]

Hi Gmatfor days,

After pondering over this I have come to the conclusion that its the HCF we are talking about (the question may be incorrect) and not the LCM. That is the only way there can be an answer, 8mths = x, 4 mths = y, difference = 4, HCF = 4

This question was sent from a friend of mine by mail. You can access questions like this one at Ascent Education's group ascent4cat@yahoogroups.com - messages

Shivani

[gmatfordays]

I figured it had to be a misprint.. I was honestly bashing my head against the wall trying to come up with an answer.

Thanks for the clarification.