[MaskedMenace]

Originally Posted by ankur123xyz

if |x-4| + |y+4| =4 .how many integer values can the set (x,y) have?
a.infinite
b.5
c.16
d.9
e.25

Number of integral values is the area inside it.

|x| + |y| = 4 => area is 16 units.

[Whats in a name]

Originally Posted by MaskedMenace

Number of integral values is the area inside it.

|x| + |y| = 4 => area is 16 units.

Hey, Masked,

Is there any specific deductions/logic behind your conclusion ? Pls elaborate

Regards
Soham

[dipsleo88]

masked ,soham mera bhi doubt kar do..its n d previous page plss..doubt clear kardo

[anoopkumars]

Originally Posted by MaskedMenace

a^n + b^n can be written as (a+b)*(ba^n-1 + ...)

write each of the terms as a^3 + b^3 = (a+b)(a^2 - ab + b^2)

17^3 + 19^3 = 17+19 = 36 divisible by 36 => R is 0

23^3 + 25^3 + 29^3 + 31^3 = 36 +36 => R is 0

35^3 + 37^3 + 41^3+43^3 + 47^3 + 49^3 = 72 + 84 + 96 => R is 0

For 2 terms remainder is 0, for four terms remainder is 0,for six terms remainder is 0,for 8terms remainder is 0,for 10terms remainder is 0 and so on ..

sorry if i'm disturbing . i actually didnt get this step
23^3 + 25^3 + 29^3 + 31^3 = 36 +36 => R is 0
pls help

[Whats in a name]

Originally Posted by MaskedMenace

Number of integral values is the area inside it.

|x| + |y| = 4 => area is 16 units.

And one more thing.... had the equation been... |X + 4| + |Y + 4| = 4, then u cud have taken, shifting of origin funda... but here it's |X - 4| + |Y + 4| = 4

[MaskedMenace]

Originally Posted by dipsleo88

There r 5 blue socks, 4 red socks and 3 green socks,in debu's wardrobe. he has to select 4 socks from this set. in how many ways can he do so??

the ans is 12C4.

now comin to my doubt,

in how many ways can a selection be made of 5 letters out of 5A,4B,3C,2D,1E??

y cant i write the ans as 15C5???

please xplain..is it something related to identical things and all?? pls clear my doubt.

it is 15c5, there are no conditions hence pick any 5 from 15.

I guess selection is made and with replacement,check that.

[MaskedMenace]

Originally Posted by anoopkumars

sorry if i'm disturbing . i actually didnt get this step
23^3 + 25^3 + 29^3 + 31^3 = 36 +36 => R is 0
pls help

23^3 + 25^3 = 48*(25^2 -25*23 + 23^2) mod 36 = 12*(3k) mod 36 = 0

29^3+31^3 = 60*(29^2 - 29*31 + 31^2) mod 36 = 24*(3k) mod 36 = 0

[vivgrn]

Originally Posted by MaskedMenace

it is 15c5, there are no conditions hence pick any 5 from 15.

I guess selection is made and with replacement,check that.

i don't understand how come in the socks question you are getting 12C4?
green socks , even though they may be belonging to any pair , are identical in nature. While your approach takes them as an independant entity.
Can you please explain your approach for the socks question?

[dillipmina]

[QUOTE=kinscool;1584718]

Originally Posted by pari16

Yup...but clock questions are based normally on the analog clocks.
So i think it should be 1 a.m. on Wednesday.

If it were digital, the clock would have to lose 24 hrs and hence it would show the correct time after 144 hrs i.e. 6 days = Saturday 1 a.m.[/QUOTE]
why is that?

10 mins are lost each hour.........24 hours would be lost in 24*60/10=144 hours........144 hours means 6 days.........So the actual time is 1 am Saturday but the clock shows 1 am Friday......

[raizada.amit]

which material to refer for no. system? I guess it has a lot of weightage in CAT