K = wxyz, where w, x, y, z are prime numbers. Not including 1 and K, how many factors does K have?
I don't know the options for this questions ....
help me to solve this problem
Number theory.....
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 shovan85
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K=wxyz
Assuming w,x,y and z are the digits of k then
w,x,y and z can be a value from [2,3,5,7]
So the number of factors will be varying from number to number as we can form 96 different numbers using the 4 digits(Repetition allowed).
Can u please review the question?
Assuming w,x,y and z are the digits of k then
w,x,y and z can be a value from [2,3,5,7]
So the number of factors will be varying from number to number as we can form 96 different numbers using the 4 digits(Repetition allowed).
Can u please review the question?

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Since nothing is mentioned in the question about the power to which w, x, y, z are raised, i assume it is 1.shovan85 wrote:How? Please explain in detail!!lokesh r wrote:16 must the be the answer.
So using the formula
say N=w^1 x x^1 x y^1 x z^1
No of factors of N is = (1+1)x(1+1)x(1+1)x(1+1) = 2x2x2x2=16
 AtifS
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Not getting it... I was actually predicting that factors are 12 as it is a 4digit number and max can be 7777 (as 7 is the biggest prime number out of first 10 digits) and 2^12 gives 4096 but 2^13 gives 8192 which is larger than 7777.
But I am not sure I am right.
Any expert with a detailed nice explanation??
But I am not sure I am right.
Any expert with a detailed nice explanation??
I am not perfect
K = wxyz, where w, x, y, z are prime numbers. Not including 1 and K, how many factors does K have?
Answer is 22
w, x, y, and z these 4 are factors of K. Also 6 more, wx,wy,wz,xy,xz,yz. And wxy,wxz,wyz (3) each for x, y, and z also which equals 12.
= 4+6+12 = 22
Answer is 22
w, x, y, and z these 4 are factors of K. Also 6 more, wx,wy,wz,xy,xz,yz. And wxy,wxz,wyz (3) each for x, y, and z also which equals 12.
= 4+6+12 = 22

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i only count 14 factor without including 1 and kpzazz12 wrote:K = wxyz, where w, x, y, z are prime numbers. Not including 1 and K, how many factors does K have?
I don't know the options for this questions ....
help me to solve this problem
k=xyzw so k can be divisible by w,y,x,z,wx,wy,wz,xy,xz,zy,wxy,wxz,xyz
dunno how you guy find 16 and 22 and cant understand why....

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