x/3 is between 3 and 100, and it is the square of a prime

Question

x/3 is between 3 and 100, and it is the square of a prime number. How many such x are possible?

Damager · Answer

x/3 is between 3 and 100, and it is the square of a prime number. How many such x are possible?



x/3=squre of prime (b/w 3-100)
x/3= 4 , 9, ,12, 25,49
 
5 numbers

mkl_in_2001 · Answer

it should be 4 ..my last post was wrong sorry
x/3=4,9,25,49

MBAlad · Answer

Is x/3 the square of a prime or x itself?

If x itself then x is between 9 - 300

Square of primes = 9, 25, 49, 121, 169, 289

So 6 possible numbers.

OA?

johnycute · Answer

Hi mkl_in_2001,

Your second answer is correct.

Can u explain bit more....?

MBAlad · Answer

If the answer is 4 and it is x/3 that is the square of the prime number then what is significance of having x/3 rather than just using x?

mkl_in_2001 · Answer

x/3 is between 3 and 100, and it is the square of a prime number. How many such x are possible ?

treat x/3 as any number N ;3<N<100
prime squares between 2 and 100 are 
 =2^2,3^2,5^2,7^2 
= 4,9,25,49
x = 12,27,75,147 (insignificant)

The next prime i.e 11 will make x/3> 100 (11^2=121 ) so 7^2 is the limit.
i.e 4 such x are possible . Hope its clear now.

tennis1ball · Answer

Most likely it is saying x is a square of a prime number.

answer is 5.

jfd1244 · Answer

I'm still not sure about your explainations but i do get 5 for an answer. When the question states that x/3 is between 3 and 100 and that x is the square of a prime #. 
I get 25, 49, 121, 169, 289...all those numbers when divided by 3 are between 3 and 100...4/3 is and 9/3 are less than or equal to 3 there for they are not between 3 and 100...I get 5 for an answer too but that's how I interpreted the question

MBAlad · Answer

That's how I interpreted it - I guess if you discount 9 on the basis that it's "between" and "not inclusive of" then I get 5:

25, 49, 121, 169, 289

mkl_in_2001 · Answer

The question says x/3 is between 3 and 100, and it is the square of a prime number i.e x/3 is the square of a prime number NOT x;
this is the key .

MBAlad · Answer

Where is the question from?

It would just seem that there'd be no point in using x/3 instead of x if it is x/3 that is the square of the prime. Unless it's a double bluff!!

x/3 is between 3 and 100, and it is the square of a prime

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