Q.21

[Manish Salian]

Hi,

Here are the scores update after a long time. Piyush has caught up with Anil...

Anil: 37 points (-5 for Q.64, Q.62, Q.43, Q.44, Q.40, Q.28 and -2 for Q.59, Q.32)
Piyush: 34 (-2 for Q.62, Q.43, Q.44 and Q.32)
Robin: 22 points (-5 for Q.38)
Minnat: 18 points (-2 for Q.62, -2 for Q.61)
Abhinav: 11 points
Kumar: 8 points (-2 for Q.40, Q.28)
Rishabh: 7 points (-5 for Q.37, Q.32 and -2 for Q.64, Q.44, Q.40, Q.38)
Mohammed: 7 points (-2 for Q.52, -5 for Q.39)
Ruchira: 3 points (-2 for Q.54)
Lajja: 2 points
Ankita: 0 points (-5 for Q.54, -2 for Q.39)
Nisha: 0 points (-5 for Q.63)
Mubin: -2 points (-2 for Q.39)

Here is your last question, with old rules appicable i.e. with negative marking.

Q.21.

At their grand mother Shivanandini's birthday celebration, Shivanand and Shivsadanand naturally reflected on their own ages and that of their elders. They soon realised that this was a unique occasion. Shivsadanand's age could be obtained from his old brother Shivanand's age by reversing its digits, while their father Shivanandan's age was similarly related to grandmother Shivanandini's age. But even more surprising was the fact that the product of Shivsadanand's age and Shivanandini's age was equal to the product of Shivanand's age and Shivanandan's age. As if it wasn't enough, Shivsadanand is half his father's age and Shivanand is half his grand mother's age.

Now tell me how old they were!

Deadline: Sunday evening

Regards,

Manish sir

[PiyushTantia]

Hello Sir,
Thanks for giving some more questions…….

Here’s the answer….

The ages of Grandmother, father, elder brother and younger brother are 86, 68, 43 and 34 respectively.

Take granny’s age as xy, therefore father’s age becomes yx
Elder brother’s age as ab, therefore younger brother’s age becomes ba

From here we get the equation
yx * ab = xy * ba
And yx = 1/2ba
And xy = 1/2ab

So whatever ages we get must satisfy the above 3 equations….
As ba and ab are ½ of the ages of yx and xy resp…..a and b cannot be an odd number becoz if we divide it by 2 we’ll get the answer in decimals…..

Since granny’s age is the highest and a two digit even number we ignore numbers from 99 to 89 and even 88 as ba wud also be 88….. so considering the next even number 86 we try to satisfy the equations….

ab = 86, therefore ba becomes 68
xy becomes ½ of ab i.e. 43 and yx becomes ½ of ba i.e. 34

86 and 68 are interchangeable and so is 43 and 34……..
further, 86 * 34 = 68 * 43 i.e.2924

hence all the conditions are getting satisfied……so it wudn’t be wrong to take these ages……

So ages are 86, 68, 43 and 34

[AnilkumarBDaga]

I would support Piyush on this answer

[Manish Salian]

Hi Piyush,

Brilliant man!! You are absolutely right...You win 5 pioints!!

Anil you 2 points!! I am sure you can do better than "I support Piyush" campaign!! :)

Incidentally both of you have reached a score of 39!! This means there is still an opportunity for either of you to earn a 5 pointer!!

Regards,

Manish sir

[PiyushTantia]

hw Sir.....
i mean u said frm q20. onwards we get2 points and no negative....so....what's the deal...

[AnilkumarBDaga]

I don't like negative marks so much that I will give wrong answers if someone has already posted the correct answer with a detailed explanation. :D