Official Quant thread for CAT 2013

MBA CAT 2024
14983
@swapnil4ever2u said:
@ravi.theja plz explain it.. i dint get it ... though through examples it is correct.. but wats d logic ..
the logic is..a^n - b^n is always divisible by a-b. so we need to find highest a-b that will divide a^n - b^n and smallest term that'll be divisible by a^n - b^n.(General rule to be followed)

Here ur bases are common
Hence take the hcf of powers ie 100 & 120 & the hcf is (2^20) - 1
14984
@ravi.theja said:
find the remiander when 7^7^7^7.......7000 times is divided by 17
12 aa raha hai?
14985
@ravi.theja said:
bhai OA is 12..!! check karo once again..even am nt getting it
edited
14986
@ravi.theja said:
find the remiander when 7^7^7^7.......7000 times is divided by 17
Use Euler's Theorem.
Answer comes out to be 12.
14987
@Logrhythm said:
Is it 83?? 24 = 2^3*3so the squares will be of the form (12k)^2 hence, total = [1000/12] = 83
so the squares will be of the form (12k)^2

why not of the form (24k)^2

plz explain
14988
@ravi.theja said:
find the remiander when 7^7^7^7.......7000 times is divided by 17
e(17) is 16
7^7%16 = 7
7^7%17 = 12
14989
If x , y and z are the lengths of sides of a triangle and ,
k=(x^2+y^2+z^2)/(xy+yz+xz), which of the following best describes k

a) 0b)1c)0d)1
14990
@joyjitpal said:
so the squares will be of the form (12k)^2 why not of the form (24k)^2plz explain
see, we need a number which when multiplied by itself gives us at least 3 2's and 1 3....
first multiple of 3 and 2 is 6, but 6*6 = 2^2*3^2 (we need one more 2)
second multiple -> 12 = 4*3......so 12^2 yields 4 2's and 1 3....hence this is the smallest number whose sq will give us the required multiple....
hence 12k form..

hope samaj gaye hoge....
14991
@Logrhythm pura samajh me aya
thanx
14992
@bs0409 said:
If x , y and z are the lengths of sides of a triangle and ,k=(x^2+y^2+z^2)/(xy+yz+xz), which of the following best describes ka) 0
took two cases....
equilateral trngl -> 111
another trngl -> 234

option b holds best...pl let me knw if this is correct...
14993
@bs0409 said:
If x , y and z are the lengths of sides of a triangle and ,k=(x^2+y^2+z^2)/(xy+yz+xz), which of the following best describes ka) 0
b?
values put karke dekha
14994
@Logrhythm
plss explain yar m gettin 12 as oa BUT PLSS TELL UR APPraoch but not in brief
14995
@Logrhythm said:
took two cases....equilateral trngl -> 111another trngl -> 234option b holds best...pl let me knw if this is correct...
@mailtoankit said:
b?values put karke dekha
Correct...................

A four digit number numbered from 0000 to 9999 is said to be lucky, if the sum of the first two digits is equal to the sum of the last two digits. Find how many such numbers are possible ?
14996
@bs0409 said:
If x , y and z are the lengths of sides of a triangle and ,k=(x^2+y^2+z^2)/(xy+yz+xz), which of the following best describes ka) 0
b??
14997
@Logrhythm
plss explain yar m gettin 12 as oa BUT PLSS TELL UR APPraoch but not in brief
14998
@Amrofa said:
A shopkeeper makes a profit of q% by selling an object for RS 24 .had the c.p and s.p interchanged ,it would have led to a loss of 62.5q% .with the latter c.p ,what should be the new selling price to get a profit of q%?a)34.40 % b)32.5% c)25.60% d)38.4% e)none
Rs.40 i.e. None ?
14999
@bs0409 said:
If x , y and z are the lengths of sides of a triangle and ,k=(x^2+y^2+z^2)/(xy+yz+xz), which of the following best describes ka) 0
d hoga kya?
15000
@bs0409 said:
If x , y and z are the lengths of sides of a triangle and ,k=(x^2+y^2+z^2)/(xy+yz+xz), which of the following best describes ka) 0
b ? Take any triangular sides possible, thatz it.
15001
@joyjitpal
x+y>z this gves xz+yz>z^2
y+z>x this gives yx+zx>x^2
z+x>y this gives zy+xy>y^2


now add all three 2(xy+yz+xz)>x^2+y^2+z^2
k
15002
@bs0409 said:
Correct...................A four digit number numbered from 0000 to 9999 is said to be lucky, if the sum of the first two digits is equal to the sum of the last two digits. Find how many such numbers are possible ?
1^2+2^2+3^2+4^2...........+10^2 + 1^2+2^2+3^2+............+9^2
-> 670